LibreNMS: Remote Code Execution by Signal Alert Transportation Module
Summary
| CVE | CVE-2026-55182 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-26 22:16:24 UTC |
| Updated | 2026-08-26 22:16:24 UTC |
| Description | LibreNMS is a network monitoring system. In versions from 21.6.0 up to 26.5.0, the Signal alert transport is vulnerable to command injection because the signal-cli path and the Recipient field of an alert transport entry are insufficiently escaped before being passed to an exec call. An authenticated administrator can craft a transport entry whose Recipient contains shell metacharacters and whose path points to the bundled composer_wrapper.php script, which itself passes attacker-controlled input to further unsafe exec calls. By chaining these calls, the administrator can execute arbitrary operating-system commands on the LibreNMS host. This issue is fixed in version 26.5.0. |
Risk And Classification
Primary CVSS: v4.0 8.6 HIGH from [email protected]
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Problem Types: CWE-77 | CWE-77 CWE-77: Improper Neutralization of Special Elements used in a Command ('Command Injection')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 8.6 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | DECLARED | 8.6 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
NonePrivileges Required
HighUser Interaction
NoneConfidentiality
HighIntegrity
HighAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/librenms/librenms/commit/868e3b966a | [email protected] | github.com | |
| github.com/librenms/librenms/security/advisories/GHSA-c9fv-cgmm-2wg7 | [email protected] | github.com | |
| github.com/librenms/librenms/releases/tag/26.5.0 | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.