Vulnerability · Published Aug 18, 2026 · Assigned by GitHub_M
CVE-2026-73974linuxfabrik-lib: Arbitrary root file read via live --test argument (lib.lftest) across sudoers-whitelisted plugins (LPE)
Medium 5.5
In plain English
A medium-severity path traversal in lib from Linuxfabrik. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
linuxfabrik-lib provides Python modules for database access, caching, shell execution, and API integrations, and Linuxfabrik Monitoring Plugins uses its shared testing helper across check plugins. Prior to linuxfabrik-lib 6.1.0 and Linuxfabrik Monitoring Plugins 7.0.0, lib.lftest.test() treated the first or second element of a --test CSV argument as a filesystem path and returned the file contents as simulated standard output or standard error without path confinement. The hidden but production-accessible --test argument was accepted by sudo-authorized plugins, so an attacker controlling the nagios or icinga account could use check-plugins/deb-updates/deb-updates with its default QUERY=1 to disclose every line of a root-readable file. Approximately 22 other plugins exposed filtered content or a root file existence and readability oracle through the same helper, while check-plugins/network-bonding/network-bonding and check-plugins/openstack-swift-stat/openstack-swift-stat had direct read paths that bypassed the helper. The library fix confines fixture reads to the invoking plugin's unit-test directory and refuses unsafe anchors, and the plugin fix routes the two bypasses through that helper. These issues are fixed in linuxfabrik-lib 6.1.0 and Linuxfabrik Monitoring Plugins 7.0.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | linuxfabrik-lib | 6.1.0 | GHSA-rh9c-rqvg-f7pr |
| PyPI | linuxfabrik-lib | 6.1.0 | PYSEC-2026-3682 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linuxfabrik | monitoring-plugins | < 7.0.0 |
| Linuxfabrik | lib | < 6.0.1 |
Weakness: CWE-22, CWE-269 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
References
- https://github.com/Linuxfabrik/monitoring-plugins/security/advisories/GHSA-rh9c-rqvg-f7pr x_refsource_CONFIRM
- https://github.com/Linuxfabrik/lib/commit/d665042c55fae83a295ebc0023e8b77f6c473a28 x_refsource_MISC
- https://github.com/Linuxfabrik/monitoring-plugins/commit/f6680a9e4b39569f318feefdb2f51e5d18c7dad5 x_refsource_MISC
- https://github.com/Linuxfabrik/lib/releases/tag/v6.1.0 x_refsource_MISC
- https://github.com/Linuxfabrik/monitoring-plugins/releases/tag/v7.0.0 x_refsource_MISC