Keycloak: keycloak: information disclosure via oidc token introspection endpoint audience bypass

MITRE NVD CVE.ORG JSON API Print: PDF PDF

Summary

CVECVE-2026-37979
StatePUBLISHED
Assignerredhat
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-05-19 12:16:18 UTC
Updated2026-05-20 17:16:21 UTC
DescriptionA 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.

Risk And Classification

Primary CVSS: v3.1 6.5 MEDIUM from [email protected]

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

EPSS: 0.000120000 probability, percentile 0.016160000 (date 2026-05-27)

Problem Types: CWE-284 | CWE-284 CWE-284 Improper Access Control

VersionSourceTypeScoreSeverityVector
3.1[email protected]Secondary6.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
3.1CNACVSS6.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Red Hat Red Hat Build Of Keycloak 26.4 unaffected 26.4.12-1 * rpm Not specified
CNA Red Hat Red Hat Build Of Keycloak 26.4 unaffected 26.4-17 * rpm Not specified
CNA Red Hat Red Hat Build Of Keycloak 26.4 unaffected 26.4-17 * rpm Not specified
CNA Red Hat Red Hat Build Of Keycloak 26.4.12 Not specified Not specified

References

ReferenceSourceLinkTags
access.redhat.com/security/cve/CVE-2026-37979 [email protected] access.redhat.com
bugzilla.redhat.com/show_bug.cgi [email protected] bugzilla.redhat.com
access.redhat.com/errata/RHSA-2026:19596 [email protected] access.redhat.com
access.redhat.com/errata/RHSA-2026:19597 [email protected] access.redhat.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Red Hat would like to thank Herdiyan Adam Putra for reporting this issue. (en)

Additional Advisory Data

SourceTimeEvent
CNA2026-04-06T07:57:53.307ZReported to Red Hat.
CNA2026-05-19T00:00:00.000ZMade public.

Workarounds

CNA: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

© CVE.report 2026 |

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report