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 2.641.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

19 Jun 2026, 06:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-18 17:16

Updated : 2026-06-22 17:52

NVD link : CVE-2026-56020

Mitre link : CVE-2026-56020

CVE.ORG link : CVE-2026-56020

JSON object : View

Products Affected

No product.

CWE

CWE-290

Authentication Bypass by Spoofing

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