authentik is an open-source identity provider. Prior to versions 2025.12.6, 2026.2.4, and 2026.5.1, an attacker with the ability to change a source connection, and an account in one of the configured sources can log into any account. This issue has been patched in versions 2025.12.6, 2026.2.4, and 2026.5.1.
authentik is an open-source identity provider. Prior to versions 2025.12.6, 2026.2.4, and 2026.5.1, the Source stage can be bypassed by sending an empty POST. This issue has been patched in versions 2025.12.6, 2026.2.4, and 2026.5.1.
authentik is an open-source identity provider. Prior to version 2026.2.3, the WS-Federation provider validates the user-supplied wreply parameter using a raw string prefix check rather than proper URL parsing. An attacker who can craft a login link can supply a wreply value on a different origin that passes the check (e.g. https://portal.example.com.evil.tld/), causing the victim's browser to POST the signed WS-Federation login response to attacker-controlled infrastructure. This issue has been patched in version 2026.2.3.
authentik is an open-source identity provider. Prior to versions 2025.12.5, 2026.2.3, and 2026.5.1, authentik's SAML Source ACS endpoint is vulnerable to XML Signature Wrapping when validating upstream SAML responses. An attacker with any account at the upstream IdP can reuse a valid signed assertion to authenticate as another federated user. This issue has been patched in versions 2025.12.5, 2026.2.3, and 2026.5.1.