CVE-2026-55182

Name of the Vulnerable Software and Affected Versions LibreNMS versions 21.6.0 through 26.4.0

Description An authenticated administrator can execute arbitrary operating-system commands on the host server. The issue occurs because the deliverAlert function in LibreNMS/Alert/Transport/Signal.php insufficiently escapes the signal-cli path and the Recipient field before passing them to an exec call. By pointing the path to the composer wrapper.php script, which also contains unsafe exec calls, an attacker can chain these calls to achieve remote code execution.

Recommendations Update to version 26.5.0.