CVE-2026-102631

In authd before 0.7.1, the user identity matching in UpdateUser (internal/users/manager.go) resolves an incoming login by the broker-scoped provider ID, but falls back to matching the username when the provider ID does not belong to any known user, and does not reject a conflicting non-empty provider ID. If an identity provider reassigns an email address, which authd uses as the username, to a new account, the new account inherits the previous user's local UID and home directory on its next login. This allows the new user to access and modify files belonging to the previous user, including credentials such as SSH keys and cloud API tokens, and silently rebinds the local account record to the new identity. As a mitigation, administrators should lock or delete the previous user's local authd account when the corresponding IdP account is removed.

CVSS

No CVSS.

References

Link	Resource
https://bugs.launchpad.net/ubuntu/+source/authd/+bug/2168531
https://github.com/canonical/authd/pull/2067
https://ubuntu.com/security/CVE-2026-102631

Configurations

No configuration.

History

15 Oct 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-15 17:17

Updated : 2026-10-16 21:17

NVD link : CVE-2026-102631

Mitre link : CVE-2026-102631

CVE.ORG link : CVE-2026-102631

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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