The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.33.1, src/main/java/com/rabbitmq/client/impl/ValueReader.java uses ValueReader.readBytes to accept a wire-declared contentLength below Integer.MAX_VALUE and allocate a byte array before checking the bytes available in the frame. A malicious AMQP peer can send a LongString or byte-array field with type tag S and a declared length such as 0x7FFFFFFE during the pre-authentication connection.start server-properties table, causing an approximately 2 GB allocation and OutOfMemoryError before readFully consumes data. The resulting memory exhaustion can terminate the JVM and cause denial of service. This issue is fixed in version 5.33.1.
https://github.com/rabbitmq/rabbitmq-java-client/security/advisories/GHSA-68mj-5wr7-6fgg
https://github.com/rabbitmq/rabbitmq-java-client/releases/tag/v5.33.1
https://github.com/rabbitmq/rabbitmq-java-client/pull/2008
https://github.com/rabbitmq/rabbitmq-java-client/pull/2007
https://github.com/rabbitmq/rabbitmq-java-client/commit/6a87a8dcdc8b4cc4b961a7cdd388276446e5dfb2
https://github.com/rabbitmq/rabbitmq-java-client/commit/388209356c6478088efce4d8a07b68e73837a7a0
Published: 2026-08-18
Updated: 2026-08-18
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P
Severity: Medium
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 8.7
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Severity: High