goauthentik up to 2026.2.5/2026.5.4 SAML Source injection

Summaryinfo

A vulnerability was found in goauthentik authentik up to 2026.2.5/2026.5.4 and classified as critical. This affects an unknown function of the component SAML Source. Such manipulation leads to injection. This vulnerability is referenced as CVE-2026-57580. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability was found in goauthentik authentik up to 2026.2.5/2026.5.4. It has been rated as critical. Affected by this issue is an unknown code of the component SAML Source. The manipulation with an unknown input leads to a injection vulnerability. Using CWE to declare the problem leads to CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. Impacted is confidentiality, integrity, and availability. CVE summarizes:

authentik is an open-source identity provider. Prior to 2026.2.6 and 2026.5.5, an inbound SAML Source configured with the non-default USERNAME_LINK or EMAIL_LINK user-matching mode interprets an XML comment in a NameID differently from the identity provider's signed assertion. An attacker with an account on the source identity provider who can set the account's NameID can inject an XML comment that truncates the value used by authentik to the text before the comment while the signed assertion remains valid. A crafted NameID can therefore truncate to a victim's username or email and bind the attacker's external identity to the victim's existing account. This grants full takeover without the victim's password or the identity provider's private key, and the malicious link persists so later logins succeed without the comment. Sources using the default unique-identifier matching mode and authentik's outbound SAML Provider role are not affected. This issue is fixed in versions 2026.2.6 and 2026.5.5.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-57580 since 06/24/2026. The exploitation is known to be easy. The attack may be launched remotely. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1055 by the MITRE ATT&CK project.

Upgrading to version 2026.2.6 or 2026.5.5 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

• goauthentik

Name

• authentik

Version

• 2026.2.0
• 2026.2.1
• 2026.2.2
• 2026.2.3
• 2026.2.4
• 2026.2.5
• 2026.5.0
• 2026.5.1
• 2026.5.2
• 2026.5.3
• 2026.5.4

Website

• Product: https://github.com/goauthentik/authentik/

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