Medium severity · published Jun 18, 2026
CVE-2026-56022
Webmin MFA bypass
5.3
CVSS
0.6%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 46% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WE
Webmin · Webmin
before 2.640 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-56022
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-56022
Release Notes
https://github.com/webmin/webmin/releases/tag/2.640
VDB Entry
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-169-02.json
Vendor Advisory
https://webmin.com/security/#webmin-prior-to-2640
VDB Entry
https://www.cve.org/CVERecord?id=CVE-2026-56022
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