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.

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 use…

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.

Affected products

Webmin — versions 0, 2.641

Weakness classification (CWE)

CWE-290 — Authentication Bypass by Spoofing

References

9119a7d8-5eab-497f-8521-727c672e3725 (release-notes)
9119a7d8-5eab-497f-8521-727c672e3725 (release-notes)
9119a7d8-5eab-497f-8521-727c672e3725
9119a7d8-5eab-497f-8521-727c672e3725 (vdb-entry)

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.