Medium Open redirect

CVE-2026-41569 — authentik: WS-Federation wreply origin bypass can exfiltrate signed login responses to attacker-controlled endpoints

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.

Published Jun 2, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.3% (30-day exploitation probability)+4
Technical severity (medium)+3
Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.32%

ahead of 24% of scored CVEs · Oct 14, 2026

Affects

Goauthentik

Authentik

CVSS base

6.1

Medium · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

Yes

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

Documented mitigation — github.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Goauthentik Authentik).
The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
Apply the documented mitigations until a definitive fix is available.
Exploitation requires user interaction: tighten email/web filtering and warn affected users.
Search available logs for exploit probes matching the vulnerability class (open redirect), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Goauthentik	Authentik	< 2026.2.3	Vulnerable	NIST National Vulnerability Database
Goauthentik	Authentik	version < 2026.2.3	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

None

User interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
6.9	CVSS 4.0	Medium	—	—	security-advisories@github.com via NIST National Vulnerability Database
6.9	CVSS 4.0	Medium	—	—	GitHub_M via CVE Program (cve.org) e CISA ADP
6.1	CVSS 3.1	Medium	2.8	2.7	nvd@nist.gov via NIST National Vulnerability Database

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-601 · Open Redirect

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.32%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).

web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

2026
Affected products added · goauthentik/authentik
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
Fix documented
Oct 13, 2026 · NIST National Vulnerability Database
CVSS changed · 6.1
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Jun 2, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

github.com/goauthentik/authentik/security/advisories/GHSA-995q-72cw-cfw3
Mitigation, Vendor Advisory, x_refsource_CONFIRM, NIST National Vulnerability Database

Elsewhere on this site

Goauthentik
every CVE for this vendor

Open redirect
same class

CWE-601
other pages naming this weakness

Related CVEs (same products)

High CVE-2026-49443 authentik: `UserSourceConnection.user` and `GroupSourceConnection.group` are changeable through the API Jun 2, 2026
Critical CVE-2026-49448 authentik: SourceStage bypass via empty POST Jun 2, 2026
Critical CVE-2026-42849 authentik: Reflected XSS in SFE AutosubmitStage allows IDP account takeover Jun 2, 2026
High CVE-2026-47201 authentik: XML Signature Wrapping in SAML Source ACS allows authentication as arbitrary federated user Jun 2, 2026
High CVE-2026-41577 authentik: SAML source does not validate Conditions, timing, or audience on assertions Jun 2, 2026
High CVE-2026-40172 authentik: Privilege Escalation via User PATCH: Superuser Group Assignment Bypasses enable_group_superuser May 22, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-41569 is "authentik: WS-Federation wreply origin bypass can exfiltrate signed login responses to attacker-controlled endpoints", rated Medium. It affects Authentik (Goauthentik); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.1 describes technical severity. EPSS 0.32% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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