CVE-2026-55106
authentik is an open-source identity provider. Prior to 2026.2.6 and 2026.5.5, a diagnostic action on the LDAP Source API does not enforce the object-level read-authorization filter used by the rest of the API. Any party able to reach the API, including an unauthenticated client, can invoke the diagnostic action against a configured LDAP Source. The server then connects to the upstream directory using the source's configured bind credentials and returns a bounded set of directory entries. The response exposes the distinguished names of those entries and the names of the attributes present on them, revealing directory structure, naming conventions, and the existence of specific accounts and groups, but not attribute values. Deployments without a configured LDAP Source are not affected. This issue is fixed in versions 2026.2.6 and 2026.5.5.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 16% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 5.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N- Weakness
- CWE-862
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-08-18
- Last modified
- 2026-09-08
- Sources
- NVD
References
- https://github.com/goauthentik/authentik/commit/e638de23217480854ec5e48ca6fceae479321f99
- https://github.com/goauthentik/authentik/commit/fc336da4bd32bef52800c77d91aa0b82c5533041
- https://github.com/goauthentik/authentik/pull/24055
- https://github.com/goauthentik/authentik/pull/24060
- https://github.com/goauthentik/authentik/releases/tag/version/2026.2.6
- https://github.com/goauthentik/authentik/releases/tag/version/2026.5.5
- https://github.com/goauthentik/authentik/security/advisories/GHSA-h8ff-c3h7-2gf8