The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.36.0, ValueReader.readShortstr decodes malformed UTF-8 bytes into replacement characters that can re-encode beyond the AMQP shortstr limit enforced by ValueWriter.writeShortstr. An attacker who can submit an RPC message with a malformed echoed property can cause reply publication in RpcServer.mainloop() or tutorial-style consumers to throw an unchecked exception before acknowledgement. The broker requeues the message, allowing the same message to disable replacement consumers until the queue is purged. This issue is fixed in version 5.36.0.
Weakness
The product does not properly encode or decode the data, resulting in unexpected values.
Potential Mitigations
- Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/120.html
- https://cwe.mitre.org/data/definitions/267.html
- https://cwe.mitre.org/data/definitions/3.html
- https://cwe.mitre.org/data/definitions/52.html
- https://cwe.mitre.org/data/definitions/53.html
- https://cwe.mitre.org/data/definitions/64.html
- https://cwe.mitre.org/data/definitions/71.html
- https://cwe.mitre.org/data/definitions/72.html
- https://cwe.mitre.org/data/definitions/78.html
- https://cwe.mitre.org/data/definitions/80.html
References
- https://github.com/rabbitmq/rabbitmq-java-client/commit/b8bd750fa8c90690e859b18d6343b34421309020
- https://github.com/rabbitmq/rabbitmq-java-client/pull/2065
- https://github.com/rabbitmq/rabbitmq-java-client/releases/tag/v5.36.0
- https://github.com/rabbitmq/rabbitmq-java-client/security/advisories/GHSA-7822-rcf6-97fx
- https://github.com/rabbitmq/rabbitmq-java-client/security/advisories/GHSA-7822-rcf6-97fx