ctipilot.ch

Cisco Catalyst SD-WAN Manager pre-auth RCE (UAT-8616 prior exploitation, Feb 2026)

cve · CVE-2026-20127

Coverage timeline
2
first 2026-05-15 → last 2026-06-27
Peak priority
high
1 high · 1 notable
Sources cited
4
4 hosts
Sections touched
2
updates, weekly-top-stories
Co-occurring entities
2
see Related entities below
ATT&CK techniques
3
pinned v19.1 · see below

ATT&CK techniques

3 techniques observed across 1 entry — derived from entry metadata and body evidence, never asserted without a published entry behind it · pinned to MITRE ATT&CK v19.1 · compare on the matrix · Navigator layer (JSON)

Initial Access TA0001

T1078Valid Accounts×1

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: 2026-06-01/cve-2026-20245-cisco-catalyst-sd-wan-manager-no-patch-zero-d · ATT&CK page ↗

T1190Exploit Public-Facing Application×1

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: 2026-06-01/cve-2026-20245-cisco-catalyst-sd-wan-manager-no-patch-zero-d · ATT&CK page ↗

Execution TA0002

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: 2026-06-01/cve-2026-20245-cisco-catalyst-sd-wan-manager-no-patch-zero-d · ATT&CK page ↗

Persistence TA0003

T1078Valid Accounts×1

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: 2026-06-01/cve-2026-20245-cisco-catalyst-sd-wan-manager-no-patch-zero-d · ATT&CK page ↗

Privilege Escalation TA0004

T1078Valid Accounts×1

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: 2026-06-01/cve-2026-20245-cisco-catalyst-sd-wan-manager-no-patch-zero-d · ATT&CK page ↗

Stealth TA0005

T1078Valid Accounts×1

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: 2026-06-01/cve-2026-20245-cisco-catalyst-sd-wan-manager-no-patch-zero-d · ATT&CK page ↗

Story timeline

  1. 2026-06-27Mandiant documents the full Cisco Catalyst SD-WAN exploitation chain — CSV-injection to a root backdoor
    updates
  2. 2026-06-01CVE-2026-20245 — Cisco Catalyst SD-WAN Manager: no-patch zero-day chain confirmed to push malicious configs to edge devices
    weekly-top-stories

Where this entity is cited

  • weekly-top-stories1
  • updates1

Source distribution

  • cloud.google.com1 (25%)
  • helpnetsecurity.com1 (25%)
  • sec.cloudapps.cisco.com1 (25%)
  • security-hub.ncsc.admin.ch1 (25%)

Co-occurring entities

Derived — referenced by the same focused operational entries (weekly summaries and report roundups don't count); ×N counts the shared entries.

Entries about Cisco Catalyst SD-WAN Manager pre-auth RCE (UAT-8616 prior exploitation, Feb 2026) (2)

2026-06-27 · view entry permalink →

NOTABLECVE-2026-20127 +2exploitedupdate

Mandiant documents the full Cisco Catalyst SD-WAN exploitation chain — CSV-injection to a root backdoor

UPDATE · originally covered Mandiant publishes the forensic reconstruction behind Cisco SD-WAN Manager CVE-2026-20245 (2026-06-26)

Google Mandiant (GTIG) published (2026-06-24) the first complete TTP chain for the Cisco Catalyst SD-WAN Manager zero-day activity, observed at a service-provider victim from late 2025 into 2026 (Google Mandiant, 2026-06-24). NCSC-CH amended its Security Hub post to add the report on 2026-06-25 (NCSC-CH Security Hub post 12579).

The chain: authentication bypass via CVE-2026-20182/CVE-2026-20127 (rogue peering connection), then privilege escalation via CVE-2026-20245 — a malicious evil_tenant.csv uploaded through the request tenant-upload CLI carries unsanitised shell commands that append a troot root user to /etc/passwd and /etc/shadow, after which the actor reverts configuration changes and deletes the file for anti-forensics. This gives defenders concrete hunts the earlier advisory could not: search SD-WAN Manager instances for unexpected /etc/passwd additions, evil_tenant.csv artefacts, and request tenant-upload execution in CLI logs.

UPDATE (originally covered 2026-06-26): Google Mandiant (GTIG) published (2026-06-24) the first complete TTP chain for the Cisco Catalyst SD-WAN Manager zero-day activity, observed at a service-provider victim from late 2025 into 2026 (Google Mandiant, 2026-06-24).

ctipilot v2 brief (migrated)
vulnerability27 Jun 05:17Zmulti-sourceOpen finding ↗

2026-06-01 · view entry permalink →

HIGHCVE-2026-20245 +2exploited

CVE-2026-20245 — Cisco Catalyst SD-WAN Manager: no-patch zero-day chain confirmed to push malicious configs to edge devices

If you did nothing this week: attackers with netadmin access to your Catalyst SD-WAN Manager can execute arbitrary commands as root and, per NCSC-CH's 5 June advisory update, push malicious configurations to every downstream edge device. No patch exists.

CVE-2026-20245 is a command injection in SD-WAN Manager's CLI file-upload handler (Cisco PSIRT; daily 2026-06-06). An authenticated attacker with netadmin privileges injects arbitrary OS commands that execute as root (T1059.004). In observed limited incidents, exploitation of CVE-2026-20245 resulted in malicious configurations pushed to downstream edge devices — extending attacker control from the management plane into the forwarding plane (NCSC-CH advisory 12579, updated 2026-06-05). The realistic attack path is a three-CVE chain: CVE-2026-20182 provides unauthenticated management-interface access (T1190), CVE-2026-20127 escalates to netadmin (T1078), and CVE-2026-20245 executes OS commands as root. The first two CVEs are patched in post-14-May SD-WAN Manager builds; CVE-2026-20245 has no fix — Cisco's only guidance is management-plane access restriction.

The forwarding-plane impact is the operationally critical new fact from this week: in transit-mode SD-WAN deployments, attacker-controlled edge-device configurations can cascade into routing-table manipulation, traffic interception, and service disruption across every site managed from the compromised Manager instance. Defender actions: apply the post-14-May SD-WAN Manager builds (patches chain entry points CVE-2026-20182/20127); ACL the management interface to a dedicated management VLAN; enforce MFA for netadmin and rotate Manager credentials; hunt the CLI audit log for anomalous file-upload events; and treat any unscheduled edge-device config-push as a hunting trigger.

If you did nothing this week: attackers with netadmin access to your Catalyst SD-WAN Manager can execute arbitrary commands as root and, per NCSC-CH's 5 June advisory update, push malicious configurations to every downstream edge device.

ctipilot v2 brief (migrated)
synthesis01 Jun 05:00Zmulti-sourceOpen finding ↗