CVE-2026-126780

Description

Webmin through 2.670 contains a privilege escalation vulnerability in acl/save_group.cgi that allows delegated administrators to grant unauthorized modules by submitting arbitrary module lists in the mod parameter. Attackers with Webmin Users module access can create or edit groups holding modules like Command Shell and assign themselves membership to execute commands as root.

References

• https://github.com/webmin/webmin/blob/2.670/acl/save_group.cgi#L83
• https://github.com/webmin/webmin/commit/be54ba38c3b86a3647a62327e1de81d5d0db098a
• https://github.com/webmin/webmin/commit/c861e308f4ee4cff1795ccc7621fc75623e1bb90
• https://www.vulncheck.com/advisories/webmin-through-2.670-privilege-escalation-via-acl-save-group-cgi