authentik: WS-Federation wreply origin bypass can exfiltrate signed login responses to attacker-controlled endpoints
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.9epss 0.2%
exploitation probability
0.2%top 91% of all CVEs
observed exploitation
nono source reports it
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.
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
Affected products
goauthentik · authentik