Apache Camel: Camel-OAuth Cross-Scope Token Reuse via an Under-Keyed JVM-Global Client Credentials Token Cache

Use of Cache Containing Sensitive Information vulnerability in Apache Camel Oauth component.

This issue affects Apache Camel: from 4.19.0 before 4.22.2.

OAuthClientCredentialsTokenResolver obtains OAuth 2.0 bearer tokens through the client credentials grant on behalf of the components that authenticate their outbound calls with a named OAuth profile, such as camel-openai, camel-langchain4j-agent, camel-huggingface, camel-docling, camel-a2a, camel-spring-ai-chat and the IBM watsonx components, and of applications that call the OAuthClientAuthenticationFactory SPI directly. It kept the tokens it obtained in a static cache shared by every resolver instance and every CamelContext in the JVM, and keyed that cache on the token endpoint and the client ID only, although the token request also carries the client secret and the requested scope. Two profiles that share a token endpoint and a client ID but request different scopes, or authenticate with different client secrets, therefore mapped to the same cache entry: the profile that resolved a token first populated the entry, and the other profile was then handed that token, with no token request made under its own configuration, for as long as the token remained valid. Token caching is enabled by default, and pointing several profiles at one identity provider client is an ordinary use of the profile support rather than an opt-in to an insecure setting. The outcome is an outbound request that carries a token issued for another profile's scope, which can grant broader authority than the calling profile was configured for, or reach a service the token was not issued for; with identity providers that derive a token's audience from the requested scope, a different scope can mean a token for a different service altogether. A profile configured with a different client secret was likewise served the token obtained with the other secret, without authenticating with its own. The profiles are configured by the deployment, which is trusted, so no untrusted input reaches the cache: the party that gains is the service that receives a token it was not meant to receive, which, if hostile or compromised, can replay that token within its scope. Reaching the issue requires a deployment that defines more than one profile sharing a token endpoint and client ID while differing in scope or client secret.

Users are recommended to upgrade to version 4.23.0, which fixes the issue. If users are on the 4.22.x releases stream, then they are suggested to upgrade to 4.22.2. The 4.19.x to 4.21.x release lines reached end of life before this issue was resolved and will not receive a fix, so deployments on them must move to a supported release. For deployments that cannot upgrade immediately, disable token caching on every OAuth profile that shares a token endpoint and client ID with another profile, by setting camel.oauth.NAME.cache-tokens=false for a named profile or camel.oauth.cache-tokens=false for the default one, so that each resolution requests a token with that profile’s own scope and client secret, at the cost of a token request on every resolution. Alternatively, register a separate client at the identity provider for each profile that needs a different scope or client secret, so that no two such profiles share a client ID.