linuxfabrik-lib: fetch() forwards credential headers across a cross-origin redirect

published 2026-07-29 3 mo ago modified 2026-10-24 15 d ago also GHSA-4jc5-g844-4x33 , PYSEC-2026-3578 , EUVD-2026-50553

cvss: 6.0; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 42%
public exploits: 0; none known

linuxfabrik-lib provides Python modules for database access, caching, shell execution, and API integrations. Prior to version 6.0.0, lib.url.fetch() followed cross-origin redirects while forwarding caller-supplied credential headers other than Authorization and Cookie, allowing a malicious redirect-capable server to receive headers such as X-Auth-Token from authenticated monitoring requests. This issue is fixed in version 6.0.0.

Patch / fix

fixed in 1 links 2

pypi linuxfabrik-lib 6.0.0

github.com/Linuxfabrik/lib@6573ff9 commit
github.com/Linuxfabrik/lib/releases/tag/v6.0.0 release

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 3 mo ago (2026-07-29)

Exploit prediction

0.50% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	6.0	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	4.0	6.0	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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected packages

ecosystem	package	affected	fixed in
pypi	linuxfabrik-lib	<6.0.0	6.0.0

Affected products

Linuxfabrik monitoring-plugins

Classification

Weakness

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
CWE-918 Server-Side Request Forgery

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary