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.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact Low

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00525.

Exploitation none

Automatable no

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Webmin Webmin unknown
Version Status Constraints
0 affected < 2.640
2.640 unaffected —

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors Products
Webmin Subscribe
Webmin Subscribe

Project Subscriptions

Vendors Products
Webmin Subscribe
Webmin Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/webmin/webmin/releases/tag/2.640 cve-icon cve-icon
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-169-02.json cve-icon cve-icon
https://webmin.com/security/#webmin-prior-to-2640 cve-icon cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-56022 cve-icon cve-icon
History

Tue, 11 Aug 2026 16:30:00 +0000

Type Values Removed Values Added
References

Tue, 11 Aug 2026 15:45:00 +0000

Type Values Removed Values Added
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 2.641. 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.
References

Wed, 24 Jun 2026 21:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Thu, 18 Jun 2026 20:15:00 +0000

Type Values Removed Values Added
First Time appeared Webmin
Webmin webmin
Vendors & Products Webmin
Webmin webmin

Thu, 18 Jun 2026 16:45:00 +0000

Type Values Removed Values Added
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 2.641.
Title Webmin MFA bypass
Weaknesses CWE-308
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N'}

cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: cisa-cg

Published:

Updated: 2026-08-11T15:33:46.054Z

Reserved: 2026-06-18T14:15:41.670Z

Link: CVE-2026-56022

cve-icon Vulnrichment

Updated: 2026-06-24T19:54:59.634Z

cve-icon NVD

Status : Undergoing Analysis

Published: 2026-06-18T17:16:35.530

Modified: 2026-08-11T16:17:33.223

Link: CVE-2026-56022

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-06-18T20:00:14Z

Weaknesses