CVE-2026-6970

authd prior to version 0.6.4 contains a logic error in primary group ID assignment that can lead to local privilege escalation. When a user's primary group ID (GID) differs from their UID, either because the account was created with authd prior to version 0.5.4 or because the primary group was manually changed via the `authctl group set-gid` command, and the user's identity provider record is updated, authd incorrectly resets the user's primary group ID to their UID upon next login. This causes newly created files and directories to be owned by the wrong group, causing denial of service issues, and potentially granting unintended access to other local users and allowing local privilege escalation.

CVSS

No CVSS.

References

Link	Resource
https://github.com/canonical/authd/commit/154b428305cb1a7a19c897626fefd09d6dde8b9f
https://github.com/canonical/authd/security/advisories/GHSA-fg3j-5w9g-hmg7

Configurations

No configuration.

History

27 Apr 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-27 16:16

Updated : 2026-04-27 18:35

NVD link : CVE-2026-6970

Mitre link : CVE-2026-6970

CVE.ORG link : CVE-2026-6970

JSON object : View

Products Affected

No product.

CWE

CWE-842

Placement of User into Incorrect Group

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