CVE-2026-69219 RabbitMQ Java client ValueReader: Oversized LongString/bytes length triggers OOM via unchecked allocation
A malicious AMQP peer can trigger an OutOfMemoryError in the RabbitMQ Java client by sending oversized length declarations, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-69219?
CVE-2026-69219 is a high-severity denial of service vulnerability in rabbitmq-java-client, published on 18 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-789
Which versions are affected by CVE-2026-69219?
2 open source packages ship an affected version, including com.rabbitmq:amqp-client.
| Package | Affected | Fixed in |
|---|---|---|
com.rabbitmq:amqp-client Maven | All versions | 5.33.1 |
com.rabbitmq:amqp-client Maven | All versions | 5.33.1 |
How do I fix CVE-2026-69219?
Upgrade com.rabbitmq:amqp-client to 5.33.1 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-69219 being exploited?
There is no known exploitation of CVE-2026-69219 in the wild and no public exploit code.
Sources
Also known as CLEANSTART-2026-BN21092, CLSA-2026-1789372046, CLSA-2026-1792593562, CLSA-2026-1792593590, DEBIAN-CVE-2026-69219, ECHO-aed7-1329-6abc and 18 more.