GHSA-rhcg-3h8r-v6vp

Suggest an improvement
Source
https://github.com/advisories/GHSA-rhcg-3h8r-v6vp
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-rhcg-3h8r-v6vp/GHSA-rhcg-3h8r-v6vp.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-rhcg-3h8r-v6vp
Aliases
Published
2026-03-11T14:54:05Z
Modified
2026-03-13T08:04:28.225333Z
Severity
  • 7.2 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
Umbraco Affected by Vertical Privilege Escalation via Missing Authorization Checks
Details

Description

A privilege escalation vulnerability has been identified in Umbraco CMS. Under certain conditions, authenticated backoffice users with permission to manage users, may be able to elevate their privileges due to insufficient authorization enforcement when modifying user group memberships.

The affected functionality does not properly validate whether a user has sufficient privileges to assign highly privileged roles.

Impact

An authenticated backoffice user may be able to escalate their privileges to Administrator level.

Successful exploitation results in full administrative control of the affected Umbraco CMS instance, including unrestricted access to content, user management, and configuration settings.

The impact is significantly mitigated by the fact that this can only be exploited by a user that has already been given access to the "Users" section in the CMS. For most Umbraco setups, such users are already also "Administrators".

Patches

The issue is patched in 16.5.1 and 17.2.2.

Workarounds

There is no workaround other than upgrading for setups where they want to have users with permission for the "Users" section without also being content with those users also being part of the "Administrators" user group.

Database specific
{
    "cwe_ids": [
        "CWE-269"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-11T14:54:05Z",
    "nvd_published_at": "2026-03-10T22:16:21Z",
    "severity": "HIGH"
}
References

Affected packages

NuGet / Umbraco.Cms

Package

Affected ranges

Type
ECOSYSTEM
Events
Introduced
15.3.1
Fixed
16.5.1

Affected versions

15.*
15.3.1
15.4.0-rc
15.4.0-rc2
15.4.0
15.4.1
15.4.2
15.4.3
15.4.4
16.*
16.0.0-rc
16.0.0-rc2
16.0.0-rc3
16.0.0-rc4
16.0.0-rc5
16.0.0-rc6
16.0.0
16.1.0-rc
16.1.0
16.1.1
16.2.0-rc
16.2.0-rc2
16.2.0
16.3.0-rc
16.3.0-rc2
16.3.0-rc3
16.3.0-rc4
16.3.0
16.3.1
16.3.2
16.3.3
16.3.4
16.4.0-rc
16.4.0-rc2
16.4.0
16.4.1
16.5.0-rc
16.5.0

Database specific

source
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-rhcg-3h8r-v6vp/GHSA-rhcg-3h8r-v6vp.json"

NuGet / Umbraco.Cms

Package

Affected ranges

Type
ECOSYSTEM
Events
Introduced
17.0.0
Fixed
17.2.2

Affected versions

17.*
17.0.0
17.0.1
17.0.2
17.1.0-rc
17.1.0
17.2.0-rc
17.2.0-rc2
17.2.0
17.2.1

Database specific

source
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-rhcg-3h8r-v6vp/GHSA-rhcg-3h8r-v6vp.json"