CVE-2026-84193 LibreNMS through 26.2.0 Stored Cross-Site Scripting via SNMP
Attackers can inject malicious JavaScript via SNMP data in LibreNMS, leading to admin credential theft and CSRF token exfiltration when pages are viewed.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-84193?
CVE-2026-84193 is a medium-severity cross-site scripting vulnerability in librenms, published on 1 Sep 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
LibreNMS through 26.2.0 contains a stored cross-site scripting vulnerability in legacy PHP template pages that render unescaped SNMP-sourced data fields including BGP peer descriptions, VRF names, process information, and SLA tags. Attackers with device management access or network access to enroll a rogue SNMP device can inject malicious JavaScript that executes when admins view affected routing and device pages, enabling credential theft and CSRF token exfiltration.
Weakness: CWE-79
Which versions are affected by CVE-2026-84193?
How do I fix CVE-2026-84193?
No fix has been published for CVE-2026-84193 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-84193 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-84193 exists.
Sources
Also known as GHSA-43px-cc38-6vvc, GHSA-v5jp-f342-234h.