CVE-2026-6647

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.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.1 / Impact : 3.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://security.docs.wso2.com/en/latest/security-announcements/security-advisories/2026/WSO2-2026-5387/

Configurations

No configuration.

History

28 Oct 2026, 20:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-28 20:18

Updated : 2026-10-29 16:08

NVD link : CVE-2026-6647

Mitre link : CVE-2026-6647

CVE.ORG link : CVE-2026-6647

JSON object : View

Products Affected

No product.

CWE

CWE-613

Insufficient Session Expiration

{"id": "CVE-2026-6647", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-6647", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-29T01:51:34.435159Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "ed10eef1-636d-4fbe-9993-6890dfa878f8", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 7.4, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "LOW", "confidentialityImpact": "LOW"}, "impactScore": 3.7, "exploitabilityScore": 3.1}]}, "affected": [{"source": "ed10eef1-636d-4fbe-9993-6890dfa878f8", "affectedData": [{"vendor": "WSO2", "product": "WSO2 Identity Server", "versions": [{"status": "affected", "version": "7.2.0", "lessThan": "7.2.0.21", "versionType": "custom"}], "defaultStatus": "unaffected"}, {"vendor": "WSO2", "product": "WSO2 Carbon OAuth", "versions": [{"status": "affected", "version": "7.0.385", "lessThan": "7.0.385.17", "versionType": "custom"}, {"status": "unaffected", "version": "7.5.23", "versionType": "custom", "lessThanOrEqual": "*"}], "packageName": "org.wso2.carbon.identity.inbound.auth.oauth2:org.wso2.carbon.identity.oauth", "defaultStatus": "unknown"}]}], "published": "2026-10-28T20:18:44.080", "references": [{"url": "https://security.docs.wso2.com/en/latest/security-announcements/security-advisories/2026/WSO2-2026-5387/", "source": "ed10eef1-636d-4fbe-9993-6890dfa878f8"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "ed10eef1-636d-4fbe-9993-6890dfa878f8", "description": [{"lang": "en", "value": "CWE-613"}]}], "descriptions": [{"lang": "en", "value": "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.\n\nA 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."}], "lastModified": "2026-10-29T16:08:42.827", "sourceIdentifier": "ed10eef1-636d-4fbe-9993-6890dfa878f8"}