CVE-2026-41569
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…
Does this matter?
Lower severity and a low EPSS score (0.19%). Track it; it rarely justifies an emergency change on its own.
Description
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
- 6.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.19% probability · 9th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-601
- Affected
- goauthentik/authentik
- Source
- security-advisories@github.com
References
- https://github.com/goauthentik/authentik/security/advisories/GHSA-995q-72cw-cfw3Mitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.