CVE-2026-69219

Summary

ValueReader.readBytes() allocates a byte array sized by a wire-declared content length without validating it against actual frame data. A malicious AMQP peer triggers OOM by declaring a ~2GB string/bytes field.

Vulnerable Code

src/main/java/com/rabbitmq/client/impl/ValueReader.java lines 83-95:

private static byte[] readBytes(final DataInputStream in) throws IOException {
    final long contentLength = unsignedExtend(in.readInt());
    if(contentLength < Integer.MAX_VALUE) {
        final byte[] buffer = new byte[(int)contentLength];  // allocates before reading
        in.readFully(buffer);
        return buffer;
    }
}

Attack Scenario

A malicious AMQP server sends a LongString field (type tag 'S') with declared length 0x7FFFFFFE (2,147,483,646). The check contentLength < Integer.MAX_VALUE passes. new byte[2147483646] attempts ~2GB allocation, causing OutOfMemoryError before readFully() attempts to read data.

The allocation size is attacker-controlled and is NOT validated against the frame size or TruncatedInputStream bounds. Exploitable pre-authentication via connection.start server-properties table.

Impact

Denial of service via JVM OutOfMemoryError. Crashes the entire JVM.

CWE

CWE-789: Memory Allocation with Excessive Size Value

Remediation

Validate contentLength against the frame's remaining bytes or the negotiated max frame size (default 131,072) before allocating.

The library allows Java code to interface to AMQP servers. Please see the specification page for more information on AMQP inter-operation and standards-conformance You will need an AMQP server, such as our very own RabbitMQ server, to use with the client library.

Security Fix(es):

The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. maxBodyLebgth was not used when receiving Message objects. Attackers could send a very large Message causing a memory overflow and triggering an OOM Error. Users of RabbitMQ may suffer from DoS attacks from RabbitMQ Java client which will ultimately exhaust the memory of the consumer. This vulnerability was patched in version 5.18.0.(CVE-2023-46120)

The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.33.0, the AMQP connection tuning path records the negotiated AMQP frame_max value, but src/main/java/com/rabbitmq/client/impl/SocketFrameHandler.java and NettyFrameHandlerFactory continue to validate broker-controlled frame payload lengths against maxInboundMessageBodySize because the negotiated limit is not applied consistently through setMaxInboundFramePayloadSize. A malicious or compromised broker can send a method frame larger than the negotiated frame_max during or after connection establishment, causing the client to allocate and decode a protocol-invalid frame instead of rejecting it with MalformedFrameException. The protocol violation can disrupt the affected connection and cause client-side denial of service. This issue is fixed in version 5.33.0.(CVE-2026-61634)

The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.31.0, inbound AMQP command assembly in src/main/java/com/rabbitmq/client/impl/CommandAssembler.java processes a content-bearing method and header whose remainingBodyBytes value is smaller than a following AMQP.FRAME_BODY payload. CommandAssembler.consumeBodyFrame subtracts the peer-controlled payload length before validating that it fits, drives remainingBodyBytes negative, and throws a raw UnsupportedOperationException instead of MalformedFrameException. A malicious or compromised broker peer can send this malformed sequence on an open nonzero channel to terminate frame processing and close the client connection, causing denial of service for work using that connection. This issue is fixed in version 5.31.0.(CVE-2026-63335)

The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.33.0, com.rabbitmq.client.ConnectionFactory.useSslProtocol() and ConnectionFactory.useSslProtocol(String) configure com.rabbitmq.client.TrustEverythingTrustManager and leave hostname verification disabled, causing arbitrary server certificates, including self-signed certificates, to be accepted. A network attacker able to intercept a TLS connection can impersonate the RabbitMQ broker, read protected AMQP traffic, and modify traffic without certificate or hostname validation. The fix changes the production TLS helpers to use the JVM default trust store and enables hostname verification, while retaining an explicitly named development-only no-verification helper. This issue is fixed in version 5.33.0.(CVE-2026-63336)

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…

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.

TuxCare rebuilt com.rabbitmq:amqp-client to address 2 CVEs. Fixed in 5.19.0-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 3 CVEs. Fixed in 5.21.0-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 1 CVE. Fixed in 5.30.0-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 3 CVEs. Fixed in 5.20.0-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 4 CVEs. Fixed in 5.7.3-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 4 CVEs. Fixed in 5.16.1-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 4 CVEs. Fixed in 5.18.0-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 3 CVEs. Fixed in 5.9.0-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 3 CVEs. Fixed in 5.13.1-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 3 CVEs. Fixed in 5.14.3-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 4 CVEs. Fixed in 5.4.3-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 4 CVEs. Fixed in 5.5.3-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 1 CVE. Fixed in 5.22.0-tuxcare.1.

TuxCare rebuilt com.rabbitmq:amqp-client to address 1 CVE. Fixed in 5.26.0-tuxcare.1.

Root has patched CVE-2026-69219 in the com.rabbitmq:amqp-client package for Root:Maven. Multiple fixed versions available.