CVE-2026-126781
Webmin through 2.670 Users File Injection via acl/cert_issue.cgi
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.
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckFix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| webmin webmin webmin/webmin
github |
≥ 0; ≤ 2.670 (affected, custom)
Other versions: unaffected |
CNA: VulnCheck |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 7.7 high |
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 | CNA: VulnCheck |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H | CNA: VulnCheck |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/webmin/webmin/commit/0c449e341746d8c445c8c7db223eac1f41755943CNA: VulnCheck · patch
- https://github.com/webmin/webmin/commit/8fb194e5fbc30a6664545d48940d03759ace9bf2CNA: VulnCheck · patch
- https://github.com/webmin/webmin/blob/2.670/acl/cert_issue.cgi#L22-L52CNA: VulnCheck · technical-description
- https://www.vulncheck.com/advisories/webmin-through-2.670-users-file-injection-via-acl-cert-issue-cgiCNA: VulnCheck · third-party-advisory
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