Vulnerability in Webmin

CVE-2026-56020

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 2.202.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (41.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 41.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-56020: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

  • Webmin — versions 2.202, 2.641, 0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-56020?
CVE-2026-56020 is a high-severity vulnerability in Webmin, classified under Authentication Bypass by Spoofing. CVSS score: 8.1/10. Published 2026-06-18.
How severe is CVE-2026-56020?
High severity. CVSS v3 base score is 8.1 out of 10.