What’s Vulnerable › Vulnerabilities
CVE-2026-6647: Incomplete OAuth Token Revocation via Case Mismatch in WSO2 Identity Server Allows Continued Access After Lifecycle Events
- Severity: high (CVSS 7.4 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-10-28 · updated 2026-10-29
- Weakness: CWE-613
Description
In deployments of WSO2 Identity Server configured with a case-insensitive user store and a case-sensitive database for identity data, mismatches in username case handling can occur. This inconsistency results in OAuth token revocation operations failing to correctly identify usernames containing mixed-case characters during certain lifecycle events, preventing tokens from being invalidated. A malicious actor can exploit this vulnerability by possessing a valid access or refresh token associated with a mixed-case username. In affected configurations, these tokens may not be revoked when expected. The actor can then leverage these unrevoked tokens, before their expiry, to continue performing actions that should have been restricted, effectively bypassing intended access controls.
Affected products
- WSO2 Identity Server: from 7.2.0 before 7.2.0.21 — fixed in 7.2.0.21
- WSO2 Carbon OAuth: from 7.0.385 before 7.0.385.17 — fixed in 7.0.385.17, 7.5.23
How to fix
Upgrade to a fixed version: WSO2 Identity Server 7.2.0.21; WSO2 Carbon OAuth 7.0.385.17, 7.5.23. Check the vendor advisory for mitigations.
References
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