CVE-2026-56020

EUVD-2026-37909
The Webmin HTTP server (miniserv.pl) allows unauthenticated attackers to impersonate any user with a configured SSL client certificate by sending a forged HTTP header. A remote attacker can spoof certificate DNs and authenticate as any user. Fixed in 2.641.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
cisa-cgCNA
8.1 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
webminwebmin
𝑥
< 2.641
CNA
Common Weakness Enumeration
References
https://github.com/webmin/webmin/releases/tag/2.641
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-169-02.json
https://webmin.com/security/#webmin-prior-to-2641
https://www.cve.org/CVERecord?id=CVE-2026-56020