{"cve":"CVE-2026-55426","nvd":{"published":"2026-08-18T21:16:36.460","modified":"2026-09-09T21:13:25.910","status":"Deferred","description":"linuxfabrik-lib provides Python modules for database access, caching, shell execution, and API integrations, and Linuxfabrik Monitoring Plugins uses those modules to run external monitoring commands. From the earliest affected releases until linuxfabrik-lib 5.0.0 and Linuxfabrik Monitoring Plugins 6.0.0, check plugins embedded user-controlled values in command strings passed to lib.shell.shell_exec(), which split strings at pipe characters and executed the resulting commands. In check-plugins/restic-check/restic-check, the --repo parameter could inject a pipe-delimited command into a constructed restic invocation, and sudo-authorized execution allowed a compromised nagios or icinga account to run that command as root. The shared library also accepted command strings and a shell parameter, while numerous plugins constructed external commands from attacker-influenced arguments. The fixes require argv lists, always use shell=False, remove pipe splitting, and reject option-like positional values through lib.shell.safe_cli_value(). These issues are fixed in linuxfabrik-lib 5.0.0 and Linuxfabrik Monitoring Plugins 6.0.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-78"],"references":["https://github.com/Linuxfabrik/lib/blob/main/CHANGELOG.md","https://github.com/Linuxfabrik/lib/releases/tag/v5.0.0","https://github.com/Linuxfabrik/monitoring-plugins/blob/main/CHANGELOG.md","https://github.com/Linuxfabrik/monitoring-plugins/commit/23bb570f41fc8d9caf30b30074bba0e3db1b357a","https://github.com/Linuxfabrik/monitoring-plugins/releases/tag/v6.0.0"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:10.689564601+00:00"},"epss":{"cve":"CVE-2026-55426","score":0.00211,"percentile":0.11364,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-798h-hpph-m24j","url":"https://osv.dev/vulnerability/GHSA-798h-hpph-m24j","summary":"Linuxfabrik Monitoring Plugins have local privilege escalation using embedded command","modified":"2026-07-13T16:43:52.595858928Z","packages":[{"ecosystem":"PyPI","name":"linuxfabrik-lib","purl":"pkg:pypi/linuxfabrik-lib","ranges":["<5.0.0"],"fixed":["5.0.0"]}]},{"id":"PYSEC-2026-2594","url":"https://osv.dev/vulnerability/PYSEC-2026-2594","summary":"Linuxfabrik Monitoring Plugins have local privilege escalation using embedded command","modified":"2026-07-13T16:32:03.335279197Z","packages":[{"ecosystem":"PyPI","name":"linuxfabrik-lib","purl":"pkg:pypi/linuxfabrik-lib","ranges":["<5.0.0"],"fixed":["5.0.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}