Siemens SIMATIC S7-300

Adversaries may search within public scan databases for information about victims that can be used during targeting. Various online services continuously publish the results of Internet scans/surveys, often harvesting information such as active IP addresses, hostnames, open ports, certificates, and even server banners.

Evidence: 2026-08-20/joint-advisory-active-threat-siemens-s7-plcs · ATT&CK page ↗

Adversaries may develop exploits that can be used during targeting. An exploit takes advantage of a bug or vulnerability in order to cause unintended or unanticipated behavior to occur on computer hardware or software. Rather than finding/modifying exploits from online or purchasing them from exploit vendors, an adversary may develop their own exploits. Adversaries may use information acquired via Vulnerabilities to focus exploit development efforts. As part of the exploit development process, adversaries may uncover exploitable vulnerabilities through methods such as fuzzing and patch analysis.

Evidence: 2026-08-20/joint-advisory-active-threat-siemens-s7-plcs · ATT&CK page ↗

Adversaries may obtain access to generative artificial intelligence (AI) tools, such as large language models (LLMs), to aid various techniques during targeting. These tools may be used to inform, bolster, and enable a variety of malicious tasks, including creating scripts, assisting social engineering, developing payloads, and to Query Public AI Services in support of Reconnaissance.

Evidence: 2026-08-20/joint-advisory-active-threat-siemens-s7-plcs · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-20/joint-advisory-active-threat-siemens-s7-plcs · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

Adversaries may attempt to manipulate features of their artifacts to make them appear legitimate or benign to users and/or security tools. Masquerading occurs when the name or location of an object, legitimate or malicious, is manipulated or abused for the sake of evading defenses and observation. This may include manipulating file metadata, tricking users into misidentifying the file type, and giving legitimate task or service names.

Evidence: 2026-08-20/joint-advisory-active-threat-siemens-s7-plcs · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-20/joint-advisory-active-threat-siemens-s7-plcs · 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

Adversaries may use Valid Accounts to log into remote machines using Secure Shell (SSH). The adversary may then perform actions as the logged-on user.

Evidence: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

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: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗

Adversaries may corrupt or wipe the disk data structures on a hard drive necessary to boot a system; targeting specific critical systems or in large numbers in a network to interrupt availability to system and network resources.

Evidence: 2026-08-09/cert-polska-private-apn-pivot-into-ot-chp-plant-shutdown · ATT&CK page ↗