Vulnerability · Published Sep 24, 2026 · Assigned by GitHub_M
CVE-2026-79766Termix: OS command injection in ACME/Let's Encrypt certificate-request handler via admin-controlled domain/email
Critical 9.1
In plain English
A critical-severity OS command injection in Termix from Termix-SSH. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities).
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Termix-SSH | Termix | >= 2.4.1, < 2.5.1 |
Weakness: CWE-78 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
References
- https://github.com/Termix-SSH/Termix/security/advisories/GHSA-pr55-25gf-5f9v x_refsource_CONFIRM
- https://github.com/Termix-SSH/Termix/pull/1067 x_refsource_MISC
- https://github.com/Termix-SSH/Termix/commit/c7a9063a72071153723e668787548766c971f029 x_refsource_MISC
- https://github.com/Termix-SSH/Termix/commit/ddbdd5c437c2296607dfaa4265d6f63fbc1ca92e x_refsource_MISC
- https://github.com/Termix-SSH/Termix/releases/tag/release-2.5.1-tag x_refsource_MISC