CVE-2026-79766 Termix-SSH CVE debrief

Who should care

Termix administrators, security teams, and IT professionals responsible for server management platforms should assess exposure and apply the fix. This includes reviewing affected versions, verifying the application of the fix in version 2.5.1, and monitoring systems for suspicious activity. Additionally, security teams should consider the potential for lateral movement and compromise of connected systems, and prioritize the remediation of affected Termix

Why it matters

CVE-2026-79766 is a critical vulnerability in Termix that allows authenticated administrators to execute arbitrary operating-system commands. The issue is fixed in version 2.5.1, and administrators should assess exposure and apply the fix to prevent potential compromise and exposure of sensitive data.

• Potential for arbitrary command execution as the Termix backend process
• Exposure of Termix databases, process secrets, stored credentials, and network reachability
• Need for verification of affected versions and application of the fix
• Potential for lateral movement and compromise of connected systems

Technical summary

CVE-2026-79766 is a critical vulnerability in Termix, allowing authenticated administrators to store malicious domain and email values that can be executed as arbitrary operating-system commands. The issue arises from the interpolation of these values into a certbot shell command in src/backend/database/routes/acme-ssl-routes.ts. Both HTTP webroot and DNS Cloudflare challenge modes are affected, and compromise exposes Termix databases, process secrets, stored credentials, and network reachability. The vulnerability has a CVSS score of 9.1 and is fixed in version 2.5.1.

Defensive priority

High priority for Termix administrators and security teams to assess exposure and apply the fix.

Recommended defensive actions

• Assess exposure by checking if Termix versions 2.4.1 to 2.5.0 are in use
• Verify if the fix in version 2.5.1 has been applied
• Monitor Termix systems for suspicious activity
• Restrict access to Termix administration interfaces
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its critical CVSS score of 9.1 and affected versions. Evidence from the CVE Program and NVD suggests that authenticated administrators can store malicious domain and email values, which can be interpolated into a certbot shell command, allowing execution of arbitrary operating-system commands as the Termix backend process. The issue is fixed in version 2.5.1. Defenders should verify affected Termix deployments, assess exposure, and apply the fix to prevent

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.