Keycloak SAML Identity Provider improper authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in Keycloak. Affected is an unknown function of the component SAML Identity Provider Handler. Executing a manipulation can lead to improper authentication. This vulnerability is handled as CVE-2026-2603. There is not any exploit available.

Detailsinfo

A vulnerability was found in Keycloak (version unknown). It has been declared as critical. This vulnerability affects an unknown function of the component SAML Identity Provider Handler. The manipulation with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at bugzilla.redhat.com. This vulnerability was named CVE-2026-2603. The exploitation appears to be easy. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 03/22/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at EUVD (EUVD-2026-12690) and CERT Bund (WID-SEC-2026-0622). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Open Source Keycloak

Productinfo

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.2
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.3
VulDB Temp Score: 6.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.1
CNA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/05/2026 Advisory disclosed
03/05/2026 +0 days VulDB entry created
03/22/2026 +17 days VulDB entry last update

Sourcesinfo

Advisory: bugzilla.redhat.com
Status: Not defined

CVE: CVE-2026-2603 (🔒)
GCVE (CVE): GCVE-0-2026-2603
GCVE (VulDB): GCVE-100-349216
EUVD: 🔒
CERT Bund: WID-SEC-2026-0622 - Keycloak: Mehrere Schwachstellen ermöglichen Umgehen von Sicherheitsvorkehrungen

Entryinfo

Created: 03/05/2026 17:56
Updated: 03/22/2026 02:49
Changes: 03/05/2026 17:56 (48), 03/08/2026 21:09 (7), 03/18/2026 08:06 (1), 03/22/2026 02:49 (13)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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