msgpack-ruby JRuby decoder makes uncapped header-count allocations; a 5-byte message forces multi-GiB OOM

Summary The JRuby implementation of msgpack msgpack gem, java platform — pure Java decoder under ext/java/ sizes containers directly from the element count written in the message header, with no cap at all: no equivalent of the C unpacker's SHRTMAX clamp since 1.7.3 and none of the buffered-bytes...

CVE-2026-126366

The msgpack-ruby gem for the JRuby platform (versions prior to 1.8.7 ) is vulnerable to a memory exhaustion issue. The msgpack-java decoder incorrectly allocates arrays and byte buffers based on attacker-controlled sizes provided in array32 , str32 , and bin32 headers without verifying the availa...

CVE-2026-66079 RabbitMQ: Pre-auth AMQP 1.0 array32 zero-width element DoS

RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6, parsearrayprimitive/2 for constructor 0x45 list0 returns an element with byte-width B = 0. The enclosing array32 parser at line 148 reads a 4-byte Count from the wire and loops Count times consumin...

PT-2026-105051

RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6, parse array primitive/2 for constructor 0x45 list0 returns an element with byte-width B = 0. The enclosing array32 parser at line 148 reads a 4-byte Count from the wire and loops Count times...

rabbitmq-server: RabbitMQ: Denial of Service via AMQP 1.0 array32 parsing

A flaw was found in RabbitMQ. An unauthenticated network attacker can exploit an issue in the AMQP 1.0 listener by sending a specially crafted 19-byte frame. This causes the system to attempt to build a list of approximately 4 billion empty elements, exhausting heap memory and terminating the...