Keycloak on Red Hat Token Introspection Endpoint access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Keycloak on Red Hat. The impacted element is an unknown function of the component Token Introspection Endpoint. Executing a manipulation can lead to access control. The identification of this vulnerability is CVE-2026-37979. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Keycloak on Red Hat (affected version unknown). It has been declared as critical. This vulnerability affects an unknown functionality of the component Token Introspection Endpoint. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. As an impact it is known to affect confidentiality. CVE summarizes:

A flaw was found in Keycloak. This access control vulnerability in Keycloak's OpenID Connect (OIDC) token introspection endpoint allows a confidential client to bypass audience restrictions. An attacker-controlled client with valid credentials can retrieve sensitive token claims intended for other resource servers, compromising the confidentiality of lightweight access tokens. This issue can be exploited remotely by any confidential client in the realm with valid credentials.

The advisory is shared for download at access.redhat.com. This vulnerability was named CVE-2026-37979 since 04/06/2026. The exploitation appears to be easy. The attack can be initiated remotely. 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 05/20/2026). The MITRE ATT&CK project declares the attack technique as T1068.

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 vulnerability database at CERT Bund (WID-SEC-2026-1612). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Red Hat Enterprise Linux
  • Open Source Keycloak

Productinfo

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.4

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (redhat): 🔒

CVSSv2info

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

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
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

04/06/2026 CVE reserved
05/19/2026 +43 days Advisory disclosed
05/19/2026 +0 days VulDB entry created
05/20/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: access.redhat.com
Status: Confirmed

CVE: CVE-2026-37979 (🔒)
GCVE (CVE): GCVE-0-2026-37979
GCVE (VulDB): GCVE-100-364624
CERT Bund: WID-SEC-2026-1612 - Keycloak: Mehrere Schwachstellen

Entryinfo

Created: 05/19/2026 15:30
Updated: 05/20/2026 14:39
Changes: 05/19/2026 15:30 (61), 05/20/2026 14:39 (7)
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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