Token Replay Vulnerability in Keycloak by Red Hat
CVE-2026-9802

6.8MEDIUM

Key Information:

Vendor

Red Hat
Status
Red Hat Build Of Keycloak
Vendor
CVE Published:
28 May 2026

What is CVE-2026-9802?

A vulnerability exists in Keycloak that could allow remote attackers to exploit a flaw related to refresh token management. When the revokeRefreshToken option is enabled alongside persistent session storage, a server restart may disrupt internal timing mechanisms. This situation enables attackers who have previously intercepted a user's refresh token to replay it, even after the token has been invalidated. Successful exploitation can provide unauthorized account access, leading to potential information disclosure or privilege escalation risks for affected users.

References

https://access.redhat.com/security/cve/CVE-2026-9802
vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2482467
issue-trackingx_refsource_REDHAT

CVSS V3.1

Score:
6.8
Severity:
MEDIUM
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Red Hat would like to thank Gyeongpyo Son for reporting this issue.
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