Webmin up to 2.670 Acl acl/save_group.cgi mod privileges management

Summaryinfo

A vulnerability, which was classified as critical, has been found in Webmin up to 2.670. This impacts an unknown function of the file acl/save_group.cgi of the component Acl. This manipulation of the argument mod causes privileges management. This vulnerability is handled as CVE-2026-126780. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as critical was found in Webmin up to 2.670. Affected by this vulnerability is an unknown functionality of the file acl/save_group.cgi of the component Acl. The manipulation of the argument mod with an unknown input leads to a privileges management vulnerability. The CWE definition for the vulnerability is CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-126780 since 11/11/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation needs additional levels of successful authentication. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/11/2026). MITRE ATT&CK project uses the attack technique T1068 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Software Management Software

Name

• Webmin

Version

• 2.670

License

• open-source

Website

• Product: https://github.com/webmin/webmin/

CPE 2.3info

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CPE 2.2info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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