Description
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.
References6
- github.com/rabbitmq/rabbitmq-java-client/commit/388209356c64780…
- github.com/rabbitmq/rabbitmq-java-client/commit/6a87a8dcdc8b4cc…
- github.com/rabbitmq/rabbitmq-java-client/pull/2007
- github.com/rabbitmq/rabbitmq-java-client/pull/2008
- github.com/rabbitmq/rabbitmq-java-client/releases/tag/v5.33.1
- github.com/rabbitmq/rabbitmq-java-client/security/advisories/GH…
Metrics
- CVSS 4.0
-
8.7
HIGH
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 55 · as of 11 November 2026
- CWE
- CWE-789
Could this be exploited in your environment?
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