CVE-2026-79766 Termix: OS command injection in ACME/Let's Encrypt certificate-request handler via admin-controlled domain/email
An authenticated administrator can inject shell commands via ACME settings, leading to arbitrary code execution on the server.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-79766?
CVE-2026-79766 is a critical command injection vulnerability in Termix-SSH Termix, published on 24 Sep 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
Termix is a web-based server management platform with SSH terminal, tunneling, and file editing capabilities. From 2.4.1 until 2.5.1, an authenticated Termix administrator can store attacker-controlled domain and email values through PATCH /users/acme-ssl-settings and trigger their interpolation into a certbot shell command through POST /users/acme-ssl-request. In src/backend/database/routes/acme-ssl-routes.ts, child_process.execSync invokes /bin/sh -c with those values only wrapped in double quotes, so shell metacharacters can execute arbitrary operating-system commands as the Termix backend process. Both HTTP webroot and DNS Cloudflare challenge modes are affected, and compromise exposes Termix databases, process secrets, stored credentials, and network reachability. This issue is fixed in version 2.5.1.
Weakness: CWE-78
Which versions are affected by CVE-2026-79766?
How do I fix CVE-2026-79766?
No fix has been published for CVE-2026-79766 yet. Limit exposure of the affected software until one is available.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-79766 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-79766 exists.
Sources
Also known as GHSA-pr55-25gf-5f9v.