VulnerabilityAnalyzed

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.

MEDIUM 6.9EPSS 0.56%

Does this matter?

Lower severity and a low EPSS score (0.56%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 4.0: 6.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.56% probability · 45th percentile
CISA KEV: Not listed
Weakness: CWE-308
Affected: webmin/webmin
Source: 9119a7d8-5eab-497f-8521-727c672e3725

References

https://github.com/webmin/webmin/releases/tag/2.640Release Notes
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-169-02.jsonVDB Entry
https://webmin.com/security/#webmin-prior-to-2640Vendor Advisory
https://www.cve.org/CVERecord?id=CVE-2026-56022VDB Entry

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.