CVE-2026-2603
Keycloak: Unauthorized authentication via disabled SAML Identity Provider
8.1
HIGH
CVSS 3.1
EPSS 0.23%
Description
A flaw was found in Keycloak. A remote attacker could bypass security controls by sending a valid SAML response from an external Identity Provider (IdP) to the Keycloak SAML endpoint for IdP-initiated broker logins. This allows the attacker to complete broker logins even when the SAML Identity Provider is disabled, leading to unauthorized authentication.
How to fix CVE-2026-2603
To remediate CVE-2026-2603, upgrade the affected package to a fixed version below.
- —upgrade to 26.5.5 or later
- —upgrade to 26.5.5 or later
Is CVE-2026-2603 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 26.5.5
- from 0, < 26.5.5
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |