SB2026042417 - Multiple vulnerabilities in LibreNMS

Description

This security bulletin contains information about 2 vulnerabilities.

1) OS Command Injection (CVE-ID: CVE-2026-6204)

CWE-ID: CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CVSSv4: 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:U/U:Clear

The vulnerability allows a remote user to execute arbitrary code.

The vulnerability exists due to improper neutralization of special elements used in an os command in the binary path settings and /ajax/netcmd endpoint when handling crafted network tool configuration and requests. A remote user can modify configured binary paths and send a crafted request to execute arbitrary code.

Exploitation requires administrative access to the application and the ability for the server to reach a remote host to download a payload.

2) Cross-site scripting (CVE-ID: CVE-2026-2728)

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear

The vulnerability allows a remote user to execute arbitrary script code in a victim's browser.

The vulnerability exists due to cross-site scripting in the ShowConfig page when rendering the rancid_repo_url configuration value in an HTML anchor tag. A remote privileged user can inject a crafted configuration value to execute arbitrary script code in a victim's browser.

User interaction is required when a user visits the affected device configuration page.

Remediation

Install update from vendor's website.

References

• https://github.com/librenms/librenms/security/advisories/GHSA-pr3g-phhr-h8fh
• https://github.com/advisories/GHSA-pr3g-phhr-h8fh
• https://github.com/librenms/librenms/security/advisories/GHSA-5gm9-622f-qcg5