Affected: WSO2 API Manager, WSO2 Traffic Manager, WSO2 Universal Gateway, WSO2 API Control Plane, WSO2 Identity Server, WSO2 Open Banking IAM, WSO2 Identity Server as Key Manager, WSO2 Open Banking AM, WSO2 Carbon OAuth

When the `allowed_scopes` configuration is enabled, the OAuth2 token introspection mechanism does not immediately invalidate a token in the cache after a revocation request. This results in a scenario where an access token that was introspected immediately before a revocation request may be returned again to the client after revocation, until the relevant cache entry is cleared.

The security consequence is that a revoked access token may be re-issued to the client during the cache lifetime. While the re-issued token is not treated as valid for API authorization, affected users may be unable to obtain a new valid access token until the cache is cleared, which can disrupt authentication flows.