Vulnerability in Webmin

CVE-2026-56022

Webmin accepts basic authentication without session cookies when an attacker provides the 'User-Agent: webmin' header, allowing bypass of additional MFA requirements. Fixed in 2.640.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (45.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 45.2% 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-2026-56022: held from 0.006 to 0.006.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

  • Webmin — versions 2.641, 0, 2.640

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-56022?
CVE-2026-56022 is a medium-severity vulnerability in Webmin, classified under Use of Single-factor Authentication. CVSS score: 5.3/10. Published 2026-06-18.
How severe is CVE-2026-56022?
Medium severity. CVSS v3 base score is 5.3 out of 10.