CVE-2026-41569CWE-601

authentik: WS-Federation wreply origin bypass can exfiltrate signed login responses to attacker-controlled endpoints

Medium · published June 2, 2026

CVSS v4.0
6.9
EPSS
0%
Percentile
24.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
6.9 · MEDIUM
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
EPSS
0.00323 · 24.1th percentile
Weakness
CWE-601 · URL Redirection to Untrusted Site ('Open Redirect')
Published
2026-06-02T20:30Z
EPSS history
Timeline
  • 02 JUN 20:30Z
    authentik: WS-Federation wreply origin bypass can exfiltrate signed login responses to attacker-controlled endpoints
    cvelistv5