# CVE-2026-126780: Webmin through 2.670 Privilege Escalation via acl/save_group.cgi

Status: published. Published: 2026-11-11. Updated: 2026-11-11.

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.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/webmin/webmin/commit/c861e308f4ee4cff1795ccc7621fc75623e1bb90
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/webmin/webmin/commit/be54ba38c3b86a3647a62327e1de81d5d0db098a

## Affected products and versions

- webmin / webmin (webmin/webmin): ≥ 0; ≤ 2.670 (affected, custom). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 8.6 (high); CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 7.2 (high); CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-269

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/webmin/webmin/commit/c861e308f4ee4cff1795ccc7621fc75623e1bb90 (CNA: VulnCheck; patch)

- https://github.com/webmin/webmin/commit/be54ba38c3b86a3647a62327e1de81d5d0db098a (CNA: VulnCheck; patch)

- https://github.com/webmin/webmin/blob/2.670/acl/save_group.cgi#L83 (CNA: VulnCheck; technical-description)

- https://www.vulncheck.com/advisories/webmin-through-2.670-privilege-escalation-via-acl-save-group-cgi (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-126780; retrieved 2026-11-11; source updated 2026-11-11

Revision: 01fc2cff13fe5b23380fc30b86bdb1ca5cfbebaea0b4cf575fe4ede1dca24e0d

Canonical: https://y2.dev/cve/CVE-2026-126780

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