Apache Camel: Camel-Keycloak Security Policy Accepts Expired Access Tokens Because Cached Token Introspection Results Are Not Bounded by the Token Expiry

Insufficient Session Expiration vulnerability in Apache Camel Keycloak component.

This issue affects Apache Camel: from 4.16.0 before 4.18.5, from 4.19.0 before 4.22.2.

When token introspection is enabled on the camel-keycloak KeycloakSecurityPolicy (useTokenIntrospection=true), the security processor validates the access token of a request by sending it to Keycloak's OAuth 2.0 token introspection endpoint, and accepts the token while the response reports it as active. The introspection endpoint reports a token as inactive once its exp (expiration) time has passed, so on this path the active flag is what enforces token expiry. Introspection results are cached by default (introspectionCacheEnabled=true, introspectionCacheTtl=60 seconds), and both cache implementations shipped with the component, ConcurrentMapTokenCache and CaffeineTokenCache, expired an entry a fixed time after it was inserted, without bounding that lifetime by the exp claim that the cached response already carried. KeycloakSecurityProcessor in turn checked only the active flag of the result, on every path that uses introspection, and never compared exp with the current time. A response cached shortly before the token expired was therefore served to later requests carrying the same token for up to the configured time-to-live after the token's expiry, and those requests were admitted with the roles and permissions the expired token had carried, although RFC 7662, which defines token introspection, states that…