SB2026072291 - Improper Authentication in Webmin

Description

This security bulletin contains information about 1 vulnerability.

1) Improper Authentication (CVE-ID: CVE-2026-42210)

CWE-ID: CWE-287 - Improper Authentication

CVSSv4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a remote user to bypass two-factor authentication.

The vulnerability exists due to improper authentication in the Basic authentication mechanism when handling authentication requests. A remote user can authenticate using Basic authentication to bypass two-factor authentication.

Exploitation requires knowledge of a valid username and password for an account configured to require a second authentication factor, typically TOTP.

Remediation

Install update from vendor's website.

References

• https://github.com/webmin/webmin/security/advisories/GHSA-qpww-fff2-6fgv
• https://github.com/webmin/webmin/commit/da18a16c84ae5c0b78cad79609cb0efb174000ec