CVE-2026-73974

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.

• github.comhttps://github.com/Linuxfabrik/lib/commit/d665042c55fae83a295ebc0023e8b77f6c473a28
• github.comhttps://github.com/Linuxfabrik/lib/releases/tag/v6.1.0
• github.comhttps://github.com/Linuxfabrik/monitoring-plugins/commit/f6680a9e4b39569f318feefdb2f51e5d18c7dad5
• github.comhttps://github.com/Linuxfabrik/monitoring-plugins/releases/tag/v7.0.0
• github.comhttps://github.com/Linuxfabrik/monitoring-plugins/security/advisories/GHSA-rh9c-rqvg-f7pr
• github.comhttps://github.com/Linuxfabrik/monitoring-plugins/security/advisories/GHSA-rh9c-rqvg-f7pr