CVE-2026-126781

high

Description

Webmin through 2.670 contains a users file injection vulnerability in acl/cert_issue.cgi that allows authenticated Webmin users to inject lines by supplying unvalidated certificate DN fields containing newlines. Attackers can end a DN field with a backslash and newline to add a second root entry with a known password hash, gaining Webmin root access after miniserv restarts.

References

https://www.vulncheck.com/advisories/webmin-through-2.670-users-file-injection-via-acl-cert-issue-cgi

https://github.com/webmin/webmin/commit/8fb194e5fbc30a6664545d48940d03759ace9bf2

https://github.com/webmin/webmin/commit/0c449e341746d8c445c8c7db223eac1f41755943

https://github.com/webmin/webmin/blob/2.670/acl/cert_issue.cgi#L22-L52

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-123775

Details

Source: Mitre, NVD

Published: 2026-11-11

Updated: 2026-11-13

Risk Information

CVSS v2

Base Score: 7.1

Vector: CVSS2#AV:N/AC:H/Au:S/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Severity: High

CVSS v4

Base Score: 7.7

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.0029