Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Linuxfabrik-lib versions before 6.0.0 are vulnerable. When fetch() follows a redirect to a different origin, it forwards caller-supplied credential headers other than Authorization and Cookie, such as X-Auth-Token or API keys, to the redirect target. An attacker controlling or able to redirect a server the client authenticates to could capture those credentials and cause authenticated requests to be sent to another host the monitoring server can reach. Upgrade to linuxfabrik-lib 6.0.0, which drops all non-transport headers on cross-origin redirects.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 6.0 | Medium | 4.0 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0050, the 43rd percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:40 UTC First seen by agentprime
- 31 Oct 2026, 14:40 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-4jc5-g844-4x33
- OSV: GHSA-4jc5-g844-4x33
- github.com/Linuxfabrik/monitoring-plugins/security/advisories/GHSA-4jc5-g844-4x33
- nvd.nist.gov/vuln/detail/CVE-2026-67435
- github.com/Linuxfabrik/lib/commit/6573ff9347e541200305d278d2663d2e54e052ff
- github.com/Linuxfabrik/lib/releases/tag/v6.0.0
- github.com/Linuxfabrik/monitoring-plugins