CVE-2026-56022: webmin Use of Single-factor Authentication
CVSS: 6.9v4.0MediumAnalyzed
Published 18-06-2026Last modified 11-08-2026
Vulnerability summary
CVE-2026-56022 is a medium (CVSS 6.9) Use of Single-factor Authentication vulnerability in webmin. EPSS estimates a 0.56% chance of exploitation in the next 30 days, higher than 45.2% of scored vulnerabilities.
CVSS score
6.9/10
010
Medium · v4.0 (CVE.org)EPSS score
0.56%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 18-06-2026PublishedVulnerability first disclosed.
- 11-08-2026Last modifiedVulnerability information updated.
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 metrics
4 scores · 2 sources · 2 versionsMedium 6.9Preferred score · CVE.org (CNA)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:NSourcesAll 2 agree
- NVDNIST6.9MediumCVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Medium 5.3Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NSourcesAll 2 agree
- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS trend
Probability
0.56%
Chance of exploitation in the next 30 days
Percentile
45%
Versus all other CVEs
30-day change
0.00 pp
From 0.56% on 20-09-2026
20-09-202620-10-2026
EPSS score0.56%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Webmin1 product
- webmin< 2.640
1 vendor · 1 product
References
4 links- github.com/webmin/webmin/releases/tag/2.640Release Notes
- raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-169-02.jsonThird Party AdvisoryVDB Entry