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

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) authd anterior a la versión 0.6.4 contiene un error lógico en la asignación del ID de grupo primario que puede conducir a una escalada de privilegios local. Cuando el ID de grupo primario (GID) de un usuario difiere de su UID, ya sea porque la cuenta fue creada con authd anterior a la versión 0.5.4 o porque el grupo primario fue cambiado manualmente a través del comando ’authctl group set-gid’, y el registro del proveedor de identidad del usuario se actualiza, authd restablece incorrectamente el ID de grupo primario del usuario a su UID en el siguiente inicio de sesión. Esto provoca que los archivos y directorios recién creados sean propiedad del grupo incorrecto, causando problemas de denegación de servicio, y potencialmente otorgando acceso no intencionado a otros usuarios locales y permitiendo la escalada de privilegios local.

Information

Published : 2026-04-27 16:16

Updated : 2026-10-26 22:10

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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