Fortinet FortiOS
product · product:fortinet-fortios single-source
Action items (6)
Do-now tasks recorded on the entries about Fortinet FortiOS, newest first. Check the date before acting on an older one.
- Audit every internet-facing FortiGate for administrator accounts and REST API keys nobody created, then terminate all administrator and VPN sessions and reset every administrator and VPN password.2026-06-18FBI and Secret Service: FortiBleed is still active…
- Patch every internet-facing FortiGate/FortiSwitchManager to the fixed builds now, and on any device that exposed CAPWAP (UDP 5246) to an untrusted network before patching, rotate VPN PSKs, SSL-VPN and LDAP bind credentials and admin passwords rather than relying on the patch alone; PivotC2's autonomous mode is built to harvest exactly those credential stores.2026-09-10CVE-2025-25249
- Search authentication-server change history on every VDI, SSL-VPN and SSO portal for edits to authentication-processing files, and re-validate that a repeated OTP value cannot authenticate; a password reset and an MFA re-enrolment do not remove this backdoor.2026-08-11CVE-2024-55591 +1
- If a Linux host has been encrypted with the .GNRA extension, preserve the encrypted files, their timestamps and the system logs before any rebuild: the advisory states the keys can be reconstructed from file timestamps, and reimaging destroys the recovery path.2026-08-11CVE-2024-55591 +1
- Enumerate every FortiGate that was running SSL-VPN while exposed to an earlier root-filesystem FortiOS vulnerability and check the SSL-VPN language-file directories for symbolic links pointing outside the user filesystem; do this regardless of when the device was patched, because this flaw specifically defeats the fix that was supposed to close that persistence path.2026-07-28CVE-2025-68686
1 older action item
- Move FortiOS 7.2, 7.0 and 6.4 devices onto a supported branch: those trains are affected in all versions and have no fixed build, so upgrading within the branch does not remediate.2026-07-28CVE-2025-68686
Defender insights
What each entry about Fortinet FortiOS tells a defender to do, newest first.
Exposure · detection
Triage
Triage · detection
Story timeline
- 2026-10-16PEERSTITCH: a memory-resident FortiGate implant installed through the FortiOS CLI path traversal CVE-2025-61624, which Fortinet lists as exploited and leaves unfixed on FortiOS 7.2, 7.0 and 6.4, after a FortiManager compromise exposed the configurations of 500+ firewalls
- 2026-09-10CVE-2025-25249, Fortinet FortiOS/FortiSwitchManager: unauthenticated CAPWAP heap overflow added to CISA KEV, actively exploited since July via the PivotC2 RAT
- 2026-09-07Recorded Future's H1 2026 Malware and Vulnerability Trends: two clusters reuse an identical post-exploitation tool stack across thirteen and ten unrelated initial CVEs
- 2026-08-11Gunra ransomware-as-a-service: a joint six-agency advisory documents FortiOS edge exploitation, a persistent MFA backdoor built from one fixed OTP value, and a Linux encryptor whose keys can be reconstructed
- 2026-07-28CVE-2025-68686, FortiOS SSL-VPN: the fix for the symlink-persistence technique is itself bypassable, and CISA now lists it as exploited
- 2026-06-18FortiBleed: an active credential-compromise campaign against internet-facing FortiGate firewalls, now locking administrators out and supplying ransomware affiliates
Hunting pivots
ATT&CK techniques (63 across 15 tactics)
63 techniques observed across 6 entries about this entity, derived from entry metadata and body evidence, never asserted without a published entry behind it · pinned to MITRE ATT&CK v20.0 · compare on the matrix · Navigator layer (JSON)
- ReconnaissanceActive Scanning
- Resource DevelopmentAcquire Infrastructure
- Initial AccessValid Accounts · Valid Accounts: Default Accounts · Valid Accounts: Domain Accounts · External Remote Services · Exploit Public-Facing Application
- ExecutionWindows Management Instrumentation · Command and Scripting Interpreter: PowerShell · Command and Scripting Interpreter: Windows Command Shell · Command and Scripting Interpreter: Unix Shell · Command and Scripting Interpreter: JavaScript · Native API
- PersistenceValid Accounts · Valid Accounts: Default Accounts · Valid Accounts: Domain Accounts · Account Manipulation · External Remote Services · Create Account: Local Account · Server Software Component: Web Shell · Modify Authentication Process: Multi-Factor Authentication
- Privilege EscalationProcess Injection: Portable Executable Injection · Process Injection: Ptrace System Calls · Exploitation for Privilege Escalation · Valid Accounts · Valid Accounts: Default Accounts · Valid Accounts: Domain Accounts · Account Manipulation
- StealthObfuscated Files or Information · Process Injection: Portable Executable Injection · Process Injection: Ptrace System Calls · Indicator Removal · Indicator Removal: Clear Command History · Valid Accounts · Valid Accounts: Default Accounts · Valid Accounts: Domain Accounts · Exploitation for Stealth · Debugger Evasion · Delay Execution · Selective Exclusion
- Defense ImpairmentModify Authentication Process: Multi-Factor Authentication · Disable or Modify Tools · Disable or Modify Tools: Clear Linux or Mac System Logs
- Credential AccessOS Credential Dumping · OS Credential Dumping: NTDS · Network Sniffing · Brute Force: Password Cracking · Brute Force: Password Spraying · Brute Force: Credential Stuffing · Steal Web Session Cookie · Unsecured Credentials: Credentials In Files · Credentials from Password Stores · Modify Authentication Process: Multi-Factor Authentication
- DiscoveryNetwork Sniffing · Network Service Discovery · System Network Connections Discovery · System Information Discovery · File and Directory Discovery · Account Discovery · Debugger Evasion
- Lateral MovementRemote Services: Remote Desktop Protocol · Remote Services: SMB/Windows Admin Shares · Use Alternate Authentication Material: Pass the Hash · Use Alternate Authentication Material: Pass the Ticket
- CollectionData from Local System · Email Collection · Data from Cloud Storage · Archive Collected Data
- Command and ControlApplication Layer Protocol: Web Protocols · Proxy · Ingress Tool Transfer · Protocol Tunneling
- ExfiltrationExfiltration Over C2 Channel · Exfiltration Over Alternative Protocol · Exfiltration Over Web Service · Exfiltration Over Web Service: Exfiltration to Cloud Storage
- ImpactData Encrypted for Impact · Inhibit System Recovery · Account Access Removal · Financial Theft
Reconnaissance TA0043
T1595Active Scanning×1
Adversaries may execute active reconnaissance scans to gather information that can be used during targeting. Active scans are those where the adversary probes victim infrastructure via network traffic, as opposed to other forms of reconnaissance that do not involve direct interaction.
Evidence: 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
Resource Development TA0042
T1583Acquire Infrastructure×1
Adversaries may buy, lease, rent, or obtain infrastructure that can be used during targeting. A wide variety of infrastructure exists for hosting and orchestrating adversary operations. Infrastructure solutions include physical or cloud servers, domains, and third-party web services. Some infrastructure providers offer free trial periods, enabling infrastructure acquisition at limited to no cost. Additionally, botnets are available for rent or purchase.
Evidence: 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
Initial Access TA0001
T1078Valid Accounts×2
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Compromised credentials may be used to bypass access controls placed on various resources on systems within the network and may even be used for persistent access to remote systems and externally available services, such as VPNs, Outlook Web Access, network devices, and remote desktop. Compromised credentials may also grant an adversary increased privilege to specific systems or access to restricted areas of the network. Adversaries may choose not to use malware or tools in conjunction with the legitimate access those credentials provide to make it harder to detect their presence.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1078.001Valid Accounts: Default Accounts×1
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Default accounts are those that are built-into an OS, such as the Guest or Administrator accounts on Windows systems. Default accounts also include default factory/provider set accounts on other types of systems, software, or devices, including the root user account in AWS, the root user account in ESXi, and the default service account in Kubernetes.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1078.002Valid Accounts: Domain Accounts×1
Adversaries may obtain and abuse credentials of a domain account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Domain accounts are those managed by Active Directory Domain Services where access and permissions are configured across systems and services that are part of that domain. Domain accounts can cover users, administrators, and services.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1133External Remote Services×3
Adversaries may leverage external-facing remote services to initially access and/or persist within a network. Remote services such as VPNs, Citrix, and other access mechanisms allow users to connect to internal enterprise network resources from external locations. There are often remote service gateways that manage connections and credential authentication for these services. Services such as Windows Remote Management and VNC can also be used externally.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1190Exploit Public-Facing Application×5
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network. The weakness in the system can be a software bug, a temporary glitch, or a misconfiguration.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · 2026-07-28/cve-2025-68686-fortios-ssl-vpn-symlink-persistence-kev · ATT&CK page ↗
Execution TA0002
T1047Windows Management Instrumentation×1
Adversaries may abuse Windows Management Instrumentation (WMI) to execute malicious commands and payloads. WMI is designed for programmers and is the infrastructure for management data and operations on Windows systems. WMI is an administration feature that provides a uniform environment to access Windows system components.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1059.001Command and Scripting Interpreter: PowerShell×2
Adversaries may abuse PowerShell commands and scripts for execution. PowerShell is a powerful interactive command-line interface and scripting environment included in the Windows operating system. PowerShell can also be installed on Linux and macOS. Adversaries can use PowerShell to perform a number of actions, including discovery of information and execution of code. Examples include the <code>Start-Process</code> cmdlet which can be used to run an executable and the <code>Invoke-Command</code> cmdlet which runs a command locally or on a remote computer (though administrator permissions are required to use PowerShell to connect to remote systems).
Evidence: 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · ATT&CK page ↗
T1059.003Command and Scripting Interpreter: Windows Command Shell×2
Adversaries may abuse the Windows command shell for execution. The Windows command shell (cmd) is the primary command prompt on Windows systems. The Windows command prompt can be used to control almost any aspect of a system, with various permission levels required for different subsets of commands. The command prompt can be invoked remotely via Remote Services such as SSH.
Evidence: 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1059.004Command and Scripting Interpreter: Unix Shell×1
Adversaries may abuse Unix shell commands and scripts for execution. Unix shells are the primary command prompt on Linux, macOS, and ESXi systems, though many variations of the Unix shell exist (e.g. sh, ash, bash, zsh, etc.) depending on the specific OS or distribution. Unix shells can control every aspect of a system, with certain commands requiring elevated privileges.
Evidence: 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · ATT&CK page ↗
T1059.007Command and Scripting Interpreter: JavaScript×1
Adversaries may abuse various implementations of JavaScript for execution. JavaScript (JS) is a platform-independent scripting language (compiled just-in-time at runtime) commonly associated with scripts in webpages, though JS can be executed in runtime environments outside the browser.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · ATT&CK page ↗
T1106Native API×1
Adversaries may interact with the native OS application programming interface (API) to execute behaviors. Native APIs provide a controlled means of calling low-level OS services within the kernel, such as those involving hardware/devices, memory, and processes. These native APIs are leveraged by the OS during system boot (when other system components are not yet initialized) as well as carrying out tasks and requests during routine operations.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Persistence TA0003
T1078Valid Accounts×2
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Compromised credentials may be used to bypass access controls placed on various resources on systems within the network and may even be used for persistent access to remote systems and externally available services, such as VPNs, Outlook Web Access, network devices, and remote desktop. Compromised credentials may also grant an adversary increased privilege to specific systems or access to restricted areas of the network. Adversaries may choose not to use malware or tools in conjunction with the legitimate access those credentials provide to make it harder to detect their presence.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1078.001Valid Accounts: Default Accounts×1
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Default accounts are those that are built-into an OS, such as the Guest or Administrator accounts on Windows systems. Default accounts also include default factory/provider set accounts on other types of systems, software, or devices, including the root user account in AWS, the root user account in ESXi, and the default service account in Kubernetes.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1078.002Valid Accounts: Domain Accounts×1
Adversaries may obtain and abuse credentials of a domain account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Domain accounts are those managed by Active Directory Domain Services where access and permissions are configured across systems and services that are part of that domain. Domain accounts can cover users, administrators, and services.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1098Account Manipulation×1
Adversaries may manipulate accounts to maintain and/or elevate access to victim systems. Account manipulation may consist of any action that preserves or modifies adversary access to a compromised account, such as modifying credentials or permission groups. These actions could also include account activity designed to subvert security policies, such as performing iterative password updates to bypass password duration policies and preserve the life of compromised credentials.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1133External Remote Services×3
Adversaries may leverage external-facing remote services to initially access and/or persist within a network. Remote services such as VPNs, Citrix, and other access mechanisms allow users to connect to internal enterprise network resources from external locations. There are often remote service gateways that manage connections and credential authentication for these services. Services such as Windows Remote Management and VNC can also be used externally.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1136.001Create Account: Local Account×1
Adversaries may create a local account to maintain access to victim systems. Local accounts are those configured by an organization for use by users, remote support, services, or for administration on a single system or service.
Evidence: 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1505.003Server Software Component: Web Shell×1
Adversaries may backdoor web servers with web shells to establish persistent access to systems. A Web shell is a Web script that is placed on an openly accessible Web server to allow an adversary to access the Web server as a gateway into a network. A Web shell may provide a set of functions to execute or a command-line interface on the system that hosts the Web server.
Evidence: 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · ATT&CK page ↗
T1556.006Modify Authentication Process: Multi-Factor Authentication×1
Adversaries may disable or modify multi-factor authentication (MFA) mechanisms to enable persistent access to compromised accounts.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Privilege Escalation TA0004
T1055.002Process Injection: Portable Executable Injection×1
Adversaries may inject portable executables (PE) into processes in order to evade process-based defenses as well as possibly elevate privileges. PE injection is a method of executing arbitrary code in the address space of a separate live process.
Evidence: 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · ATT&CK page ↗
T1055.008Process Injection: Ptrace System Calls×1
Adversaries may inject malicious code into processes via ptrace (process trace) system calls in order to evade process-based defenses as well as possibly elevate privileges. Ptrace system call injection is a method of executing arbitrary code in the address space of a separate live process.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · ATT&CK page ↗
T1068Exploitation for Privilege Escalation×1
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges. Exploitation of a software vulnerability occurs when an adversary takes advantage of a programming error in a program, service, or within the operating system software or kernel itself to execute adversary-controlled code. Security constructs such as permission levels will often hinder access to information and use of certain techniques, so adversaries will likely need to perform privilege escalation to include use of software exploitation to circumvent those restrictions.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · ATT&CK page ↗
T1078Valid Accounts×2
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Compromised credentials may be used to bypass access controls placed on various resources on systems within the network and may even be used for persistent access to remote systems and externally available services, such as VPNs, Outlook Web Access, network devices, and remote desktop. Compromised credentials may also grant an adversary increased privilege to specific systems or access to restricted areas of the network. Adversaries may choose not to use malware or tools in conjunction with the legitimate access those credentials provide to make it harder to detect their presence.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1078.001Valid Accounts: Default Accounts×1
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Default accounts are those that are built-into an OS, such as the Guest or Administrator accounts on Windows systems. Default accounts also include default factory/provider set accounts on other types of systems, software, or devices, including the root user account in AWS, the root user account in ESXi, and the default service account in Kubernetes.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1078.002Valid Accounts: Domain Accounts×1
Adversaries may obtain and abuse credentials of a domain account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Domain accounts are those managed by Active Directory Domain Services where access and permissions are configured across systems and services that are part of that domain. Domain accounts can cover users, administrators, and services.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1098Account Manipulation×1
Adversaries may manipulate accounts to maintain and/or elevate access to victim systems. Account manipulation may consist of any action that preserves or modifies adversary access to a compromised account, such as modifying credentials or permission groups. These actions could also include account activity designed to subvert security policies, such as performing iterative password updates to bypass password duration policies and preserve the life of compromised credentials.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Stealth TA0005
T1027Obfuscated Files or Information×1
Adversaries may attempt to make an executable or file difficult to discover or analyze by encrypting, encoding, or otherwise obfuscating its contents on the system or in transit. This is common behavior that can be used across different platforms and the network to evade defenses.
Evidence: 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · ATT&CK page ↗
T1055.002Process Injection: Portable Executable Injection×1
Adversaries may inject portable executables (PE) into processes in order to evade process-based defenses as well as possibly elevate privileges. PE injection is a method of executing arbitrary code in the address space of a separate live process.
Evidence: 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · ATT&CK page ↗
T1055.008Process Injection: Ptrace System Calls×1
Adversaries may inject malicious code into processes via ptrace (process trace) system calls in order to evade process-based defenses as well as possibly elevate privileges. Ptrace system call injection is a method of executing arbitrary code in the address space of a separate live process.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · ATT&CK page ↗
T1070Indicator Removal×1
Adversaries may selectively delete or modify artifacts generated to reduce indications of their presence and blend in with legitimate activity. Rather than broadly removing evidence, adversaries may target specific artifacts that appear anomalous or are likely to draw scrutiny, while leaving sufficient data intact to maintain the appearance of normal system behavior.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · ATT&CK page ↗
T1070.003Indicator Removal: Clear Command History×1
In addition to clearing system logs, an adversary may clear the command history of a compromised account to conceal the actions undertaken during an intrusion. Various command interpreters keep track of the commands users type in their terminal so that users can retrace what they've done.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1078Valid Accounts×2
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Compromised credentials may be used to bypass access controls placed on various resources on systems within the network and may even be used for persistent access to remote systems and externally available services, such as VPNs, Outlook Web Access, network devices, and remote desktop. Compromised credentials may also grant an adversary increased privilege to specific systems or access to restricted areas of the network. Adversaries may choose not to use malware or tools in conjunction with the legitimate access those credentials provide to make it harder to detect their presence.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1078.001Valid Accounts: Default Accounts×1
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Default accounts are those that are built-into an OS, such as the Guest or Administrator accounts on Windows systems. Default accounts also include default factory/provider set accounts on other types of systems, software, or devices, including the root user account in AWS, the root user account in ESXi, and the default service account in Kubernetes.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1078.002Valid Accounts: Domain Accounts×1
Adversaries may obtain and abuse credentials of a domain account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Domain accounts are those managed by Active Directory Domain Services where access and permissions are configured across systems and services that are part of that domain. Domain accounts can cover users, administrators, and services.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1211Exploitation for Stealth×1
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
Evidence: 2026-07-28/cve-2025-68686-fortios-ssl-vpn-symlink-persistence-kev · ATT&CK page ↗
T1622Debugger Evasion×1
Adversaries may employ various means to detect and avoid debuggers. Debuggers are typically used by defenders to trace and/or analyze the execution of potential malware payloads.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1678Delay Execution×1
Adversaries may employ various time-based methods to evade detection and analysis. These techniques often exploit system clocks, delays, or timing mechanisms to obscure malicious activity, blend in with benign activity, and avoid scrutiny. Adversaries can perform this behavior within virtualization/sandbox environments or natively on host systems.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1679Selective Exclusion×1
Adversaries may intentionally exclude certain files, folders, directories, file types, or system components from encryption or tampering during a ransomware or malicious payload execution. Some file extensions that adversaries may avoid encrypting include `.dll`, `.exe`, and `.lnk`.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Defense Impairment TA0112
T1556.006Modify Authentication Process: Multi-Factor Authentication×1
Adversaries may disable or modify multi-factor authentication (MFA) mechanisms to enable persistent access to compromised accounts.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1685Disable or Modify Tools×1
Adversaries may disable, degrade, or tamper with security tools or applications (e.g., endpoint detection and response (EDR) tools, intrusion detection systems (IDS), antivirus, logging agents, sensors, etc.) to impair or reduce visibility of defensive capabilities. This may include stopping specific services, killing processes, modifying or deleting tool configuration files and Registry keys, or preventing tools from updating. This may also include impairing defenses more broadly by disrupting preventative, detection, and response mechanisms across host, network, and cloud environments.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1685.006Disable or Modify Tools: Clear Linux or Mac System Logs×1
Adversaries may clear system logs to hide evidence of an intrusion. macOS and Linux both keep track of system or user-initiated actions via system logs. The majority of native system logging is stored under the `/var/log/` directory. Subfolders in this directory categorize logs by their related functions, such as:
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · ATT&CK page ↗
Credential Access TA0006
T1003OS Credential Dumping×2
Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password. Credentials can be obtained from OS caches, memory, or structures. Credentials can then be used to perform Lateral Movement and access restricted information.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1003.003OS Credential Dumping: NTDS×1
Adversaries may attempt to access or create a copy of the Active Directory domain database in order to steal credential information, as well as obtain other information about domain members such as devices, users, and access rights. By default, the NTDS file (NTDS.dit) is located in <code>%SystemRoot%\NTDS\Ntds.dit</code> of a domain controller.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1040Network Sniffing×2
Adversaries may passively sniff network traffic to capture information about an environment, including authentication material passed over the network. Network sniffing refers to using the network interface on a system to monitor or capture information sent over a wired or wireless connection. An adversary may place a network interface into promiscuous mode to passively access data in transit over the network, or use span ports to capture a larger amount of data.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1110.002Brute Force: Password Cracking×1
Adversaries may use password cracking to attempt to recover usable credentials, such as plaintext passwords, when credential material such as password hashes are obtained. OS Credential Dumping can be used to obtain password hashes, this may only get an adversary so far when Pass the Hash is not an option. Further, adversaries may leverage Data from Configuration Repository in order to obtain hashed credentials for network devices.
Evidence: 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1110.003Brute Force: Password Spraying×1
Adversaries may use a single or small list of commonly used passwords against many different accounts to attempt to acquire valid account credentials. Password spraying uses one password (e.g. 'Password01'), or a small list of commonly used passwords, that may match the complexity policy of the domain. Logins are attempted with that password against many different accounts on a network to avoid account lockouts that would normally occur when brute forcing a single account with many passwords.
Evidence: 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1110.004Brute Force: Credential Stuffing×1
Adversaries may use credentials obtained from breach dumps of unrelated accounts to gain access to target accounts through credential overlap. Occasionally, large numbers of username and password pairs are dumped online when a website or service is compromised and the user account credentials accessed. The information may be useful to an adversary attempting to compromise accounts by taking advantage of the tendency for users to use the same passwords across personal and business accounts.
Evidence: 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1539Steal Web Session Cookie×1
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials. Web applications and services often use session cookies as an authentication token after a user has authenticated to a website.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1552.001Unsecured Credentials: Credentials In Files×2
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials. These can be files created by users to store their own credentials, shared credential stores for a group of individuals, configuration files containing passwords for a system or service, or source code/binary files containing embedded passwords.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · ATT&CK page ↗
T1555Credentials from Password Stores×1
Adversaries may search for common password storage locations to obtain user credentials. Passwords are stored in several places on a system, depending on the operating system or application holding the credentials. There are also specific applications and services that store passwords to make them easier for users to manage and maintain, such as password managers and cloud secrets vaults. Once credentials are obtained, they can be used to perform lateral movement and access restricted information.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1556.006Modify Authentication Process: Multi-Factor Authentication×1
Adversaries may disable or modify multi-factor authentication (MFA) mechanisms to enable persistent access to compromised accounts.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Discovery TA0007
T1040Network Sniffing×2
Adversaries may passively sniff network traffic to capture information about an environment, including authentication material passed over the network. Network sniffing refers to using the network interface on a system to monitor or capture information sent over a wired or wireless connection. An adversary may place a network interface into promiscuous mode to passively access data in transit over the network, or use span ports to capture a larger amount of data.
Evidence: 2026-10-16/peerstitch-fortigate-implant-cve-2025-61624-fortimanager · 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1046Network Service Discovery×1
Adversaries may attempt to get a listing of services running on remote hosts and local network infrastructure devices, including those that may be vulnerable to remote software exploitation. Common methods to acquire this information include port, vulnerability, and/or wordlist scans using tools that are brought onto a system.
Evidence: 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · ATT&CK page ↗
T1049System Network Connections Discovery×1
Adversaries may attempt to get a listing of network connections to or from the compromised system they are currently accessing or from remote systems by querying for information over the network.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1082System Information Discovery×1
An adversary may attempt to get detailed information about the operating system and hardware, including version, patches, hotfixes, service packs, and architecture. Adversaries may use this information to shape follow-on behaviors, including whether or not the adversary fully infects the target and/or attempts specific actions. This behavior is distinct from Local Storage Discovery which is an adversary's discovery of local drive, disks and/or volumes.
Evidence: 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · ATT&CK page ↗
T1083File and Directory Discovery×1
Adversaries may enumerate files and directories or may search in specific locations of a host or network share for certain information within a file system. Adversaries may use the information from File and Directory Discovery during automated discovery to shape follow-on behaviors, including whether or not the adversary fully infects the target and/or attempts specific actions.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1087Account Discovery×1
Adversaries may attempt to get a listing of valid accounts, usernames, or email addresses on a system or within a compromised environment. This information can help adversaries determine which accounts exist, which can aid in follow-on behavior such as brute-forcing, spear-phishing attacks, or account takeovers (e.g., Valid Accounts).
Evidence: 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1622Debugger Evasion×1
Adversaries may employ various means to detect and avoid debuggers. Debuggers are typically used by defenders to trace and/or analyze the execution of potential malware payloads.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Lateral Movement TA0008
T1021.001Remote Services: Remote Desktop Protocol×2
Adversaries may use Valid Accounts to log into a computer using the Remote Desktop Protocol (RDP). The adversary may then perform actions as the logged-on user.
Evidence: 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1021.002Remote Services: SMB/Windows Admin Shares×1
Adversaries may use Valid Accounts to interact with a remote network share using Server Message Block (SMB). The adversary may then perform actions as the logged-on user.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1550.002Use Alternate Authentication Material: Pass the Hash×1
Adversaries may “pass the hash” using stolen password hashes to move laterally within an environment, bypassing normal system access controls. Pass the hash (PtH) is a method of authenticating as a user without having access to the user's cleartext password. This method bypasses standard authentication steps that require a cleartext password, moving directly into the portion of the authentication that uses the password hash.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1550.003Use Alternate Authentication Material: Pass the Ticket×1
Adversaries may “pass the ticket” using stolen Kerberos tickets to move laterally within an environment, bypassing normal system access controls. Pass the ticket (PtT) is a method of authenticating to a system using Kerberos tickets without having access to an account's password. Kerberos authentication can be used as the first step to lateral movement to a remote system.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Collection TA0009
T1005Data from Local System×3
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
Evidence: 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · 2026-07-28/cve-2025-68686-fortios-ssl-vpn-symlink-persistence-kev · ATT&CK page ↗
T1114Email Collection×1
Adversaries may target user email to collect sensitive information. Emails may contain sensitive data, including trade secrets or personal information, that can prove valuable to adversaries. Emails may also contain details of ongoing incident response operations, which may allow adversaries to adjust their techniques in order to maintain persistence or evade defenses. Adversaries can collect or forward email from mail servers or clients.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1530Data from Cloud Storage×1
Adversaries may access data from cloud storage.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1560Archive Collected Data×1
An adversary may compress and/or encrypt data that is collected prior to exfiltration. Compressing the data can help to obfuscate the collected data and minimize the amount of data sent over the network. Encryption can be used to hide information that is being exfiltrated from detection or make exfiltration less conspicuous upon inspection by a defender.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Command and Control TA0011
T1071.001Application Layer Protocol: Web Protocols×2
Adversaries may communicate using application layer protocols associated with web traffic to avoid detection/network filtering by blending in with existing traffic. Commands to the remote system, and often the results of those commands, will be embedded within the protocol traffic between the client and server.
Evidence: 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · ATT&CK page ↗
T1090Proxy×1
Adversaries may use a connection proxy to direct network traffic between systems or act as an intermediary for network communications to a command and control server to avoid direct connections to their infrastructure. Many tools exist that enable traffic redirection through proxies or port redirection, including HTRAN, ZXProxy, and ZXPortMap. Adversaries use these types of proxies to manage command and control communications, reduce the number of simultaneous outbound network connections, provide resiliency in the face of connection loss, or to ride over existing trusted communications paths between victims to avoid suspicion. Adversaries may chain together multiple proxies to further disguise the source of malicious traffic.
Evidence: 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · ATT&CK page ↗
T1105Ingress Tool Transfer×2
Adversaries may transfer tools or other files from an external system into a compromised environment. Tools or files may be copied from an external adversary-controlled system to the victim network through the command and control channel or through alternate protocols such as ftp. Once present, adversaries may also transfer/spread tools between victim devices within a compromised environment (i.e. Lateral Tool Transfer).
Evidence: 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1572Protocol Tunneling×1
Adversaries may tunnel network communications to and from a victim system within a separate protocol to avoid detection/network filtering and/or enable access to otherwise unreachable systems. Tunneling involves explicitly encapsulating a protocol within another. This behavior may conceal malicious traffic by blending in with existing traffic and/or provide an outer layer of encryption (similar to a VPN). Tunneling could also enable routing of network packets that would otherwise not reach their intended destination, such as SMB, RDP, or other traffic that would be filtered by network appliances or not routed over the Internet.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Exfiltration TA0010
T1041Exfiltration Over C2 Channel×2
Adversaries may steal data by exfiltrating it over an existing command and control channel. Stolen data is encoded into the normal communications channel using the same protocol as command and control communications.
Evidence: 2026-09-07/recordedfuture-h1-2026-tool-stack-reuse · 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1048Exfiltration Over Alternative Protocol×1
Adversaries may steal data by exfiltrating it over a different protocol than that of the existing command and control channel. The data may also be sent to an alternate network location from the main command and control server.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1567Exfiltration Over Web Service×1
Adversaries may use an existing, legitimate external Web service to exfiltrate data rather than their primary command and control channel. Popular Web services acting as an exfiltration mechanism may give a significant amount of cover due to the likelihood that hosts within a network are already communicating with them prior to compromise. Firewall rules may also already exist to permit traffic to these services.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1567.002Exfiltration Over Web Service: Exfiltration to Cloud Storage×1
Adversaries may exfiltrate data to a cloud storage service rather than over their primary command and control channel. Cloud storage services allow for the storage, edit, and retrieval of data from a remote cloud storage server over the Internet.
Evidence: 2026-09-10/cve-2025-25249-fortinet-fortios-capwap-pivotc2-rat · ATT&CK page ↗
Impact TA0040
T1486Data Encrypted for Impact×1
Adversaries may encrypt data on target systems or on large numbers of systems in a network to interrupt availability to system and network resources. They can attempt to render stored data inaccessible by encrypting files or data on local and remote drives and withholding access to a decryption key. This may be done in order to extract monetary compensation from a victim in exchange for decryption or a decryption key (ransomware) or to render data permanently inaccessible in cases where the key is not saved or transmitted.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1490Inhibit System Recovery×1
Adversaries may delete or remove built-in data and turn off services designed to aid in the recovery of a corrupted system to prevent recovery. This may deny access to available backups and recovery options.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
T1531Account Access Removal×1
Adversaries may interrupt availability of system and network resources by inhibiting access to accounts utilized by legitimate users. Accounts may be deleted, locked, or manipulated (ex: changed credentials, revoked permissions for SaaS platforms such as Sharepoint) to remove access to accounts. Adversaries may also subsequently log off and/or perform a System Shutdown/Reboot to set malicious changes into place.
Evidence: 2026-06-18/fortibleed-73-932-internet-facing-fortigate-devices-exposed · ATT&CK page ↗
T1657Financial Theft×1
Adversaries may steal monetary resources from targets through extortion, social engineering, technical theft, or other methods aimed at their own financial gain at the expense of the availability of these resources for victims. Financial theft is the ultimate objective of several popular campaign types including extortion by ransomware, business email compromise (BEC) and fraud, "pig butchering," bank hacking, and exploiting cryptocurrency networks.
Evidence: 2026-08-11/gunra-raas-fortios-mfa-backdoor-linux-prng-recoverable · ATT&CK page ↗
Entries about Fortinet FortiOS (6)
Earlier coverage (3)
Co-occurring entities
Derived: referenced by the same focused operational entries (weekly summaries and report roundups don't count); ×N counts the shared entries.
- Fortinet FortiProxy×2
- Fortinet FortiSwitchManager×2
- CL-STA-0954×1
- FortiBleed×1
- Fortinet FortiGate×1
- Fortinet FortiManager×1
- Fortinet FortiOS / FortiProxy authentication bypass (CWE-288), named by joint advisory AA26-222A as a primary Gunra ransomware initial-access vector, abused to create a persistent super-user account on the appliance×1
- Fortinet FortiOS / FortiProxy authentication bypass (CWE-288), named by joint advisory AA26-222A as a primary Gunra ransomware initial-access vector, abused to create a persistent super-user account on the appliance×1
Where this entity is cited
Source distribution
- cisa.gov4 (16%)
- bleepingcomputer.com3 (12%)
- fortiguard.fortinet.com3 (12%)
- fortinet.com2 (8%)
- securityweek.com2 (8%)
- socradar.io2 (8%)
- arcticwolf.com1 (4%)
- euvdservices.enisa.europa.eu1 (4%)
- other7 (28%)
All cited sources (25)
- arcticwolf.comArctic Wolfhttps://arcticwolf.com/resources/blog/active-fortibleed-campaign-impacting-fortinet-devices-across-194-countries/
- bleepingcomputer.comBleepingComputerhttps://www.bleepingcomputer.com/news/security/fbi-ongoing-fortibleed-attacks-lock-out-fortigate-vpn-admins/
- bleepingcomputer.comBleepingComputerhttps://www.bleepingcomputer.com/news/security/fortibleed-campaign-used-custom-fortigate-sniffer-to-steal-credentials/
- bleepingcomputer.comBleepingComputerhttps://www.bleepingcomputer.com/news/security/fortibleed-leak-exposes-fortinet-vpn-credentials-for-73-000-devices/
- cisa.govCISA alerthttps://www.cisa.gov/news-events/alerts/2026/06/18/cisa-urges-hardening-fortinet-devices-after-reports-credential-exposure
- cisa.govCISAhttps://www.cisa.gov/news-events/alerts/2026/07/27/cisa-adds-two-known-exploited-vulnerabilities-catalog
- cisa.govCISAhttps://www.cisa.gov/news-events/alerts/2026/09/09/cisa-adds-four-known-exploited-vulnerabilities-catalog
- cisa.govFBI, CISA, DC3, NSA, USSS and Republic of Korea National Police Agencyhttps://www.cisa.gov/news-events/cybersecurity-advisories/aa26-222a
- euvdservices.enisa.europa.euENISA EUVDhttps://euvdservices.enisa.europa.eu/api/search?text=CVE-2025-25249
- fortiguard.fortinet.comFortinet PSIRT (FG-IR-24-423)https://fortiguard.fortinet.com/psirt/FG-IR-24-423
- fortiguard.fortinet.comFortinet PSIRT (FG-IR-25-934)https://fortiguard.fortinet.com/psirt/FG-IR-25-934
- fortiguard.fortinet.comFortinet PSIRT (FG-IR-26-122)https://fortiguard.fortinet.com/psirt/FG-IR-26-122
- fortinet.comFortinet PSIRThttps://www.fortinet.com/blog/psirt-blogs/analysis-of-reported-credential-compromise-of-fortigate-devices
- fortinet.comFortinet PSIRT (blog)https://www.fortinet.com/blog/psirt-blogs/analysis-of-threat-actor-activity
- github.comGitHub Advisory Databasehttps://github.com/advisories/GHSA-mj8x-m8f5-x4w8
- ic3.govFBI and U.S. Secret Service (joint advisory JCSA-20261006-01)https://www.ic3.gov/CSA/2026/261006.pdf
- intel.breakglass.techBreakglass Intelligencehttps://intel.breakglass.tech/post/gunra-ransomware-s-linux-variant-has-a-fatal-flaw-time-seeded-rand-makes-encrypted-files-recoverable-without-paying
- recordedfuture.comRecorded Future (Insikt Group)https://www.recordedfuture.com/research/h1-2026-malware-vulnerability-trends
- securelist.comKaspersky Securelist (GReAT)https://securelist.com/strikeshark-campaign/120326/
- securityweek.comSecurityWeekhttps://www.securityweek.com/fortibleed-86000-fortinet-device-credentials-compromised/
- securityweek.comSecurityWeekhttps://www.securityweek.com/fortinet-responds-to-fortibleed-campaign/
- sentinelone.comSentinelOnehttps://www.sentinelone.com/vulnerability-database/cve-2025-25249/
- socradar.ioSOCRadar (STRU)https://socradar.io/blog/cve-2025-25249-pivotc2-fortigate-rat
- socradar.ioSOCRadarhttps://socradar.io/blog/fortibleed-fortinet-firewalls-compromised/
- unit42.paloaltonetworks.comPalo Alto Networks Unit 42https://unit42.paloaltonetworks.com/fortimanager-cve-2024-47575-peerstitch-malware/