Webmin 2FA requirement bypass

published 2026-07-20 3 mo ago modified 2026-07-23 3 mo ago also EUVD-2026-46035

cvss: 5.3; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 44%
public exploits: 0; none known

Webmin is a web-based system administration tool for Unix-like servers. Prior to version 2.640, for Webmin accounts that require a second authentication factor (typically TOTP), an attacker with knowledge of the username and password can bypass the 2FA requirement by using Basic authentication. Webmin is a web-based system administration tool for Unix-like servers. As a workaround, apply the patch from commit da18a16c84ae5c0b78cad79609cb0efb174000ec manually.

Patch / fix

fixed in 1 links 1

webmin webmin 2.640

github.com/webmin/webmin@da18a16 commit

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 3 mo ago (2026-07-20)

Exploit prediction

0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/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

Affected products

webmin webmin

Classification

Weakness

CWE-287 Improper Authentication

References

Sources

CVE List CVE-2026-42210
NVD CVE-2026-42210

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary