CVE-2026-59986: rabbitmq-c: amqp_decode_bytes size_t integer overflow bypasses bounds check on 32-bit (OOB read)

rabbitmq-c is a C-language AMQP client library for RabbitMQ. Prior to version 0.17.0, the bounds check (offset = o + len) <= encoded.len overflows when o + len > SIZEMAX on 32-bit systems. len is a uint32t read from the AMQP wire as a BYTES/UTF8 field length. The overflow wraps the check to a small value that passes, producing a decoded amqpbytest with a multi-GB .len pointing into a small frame buffer. This results in an out-of-bounds read of up to ~4GB of process memory on 32-bit systems (ARM, MIPS, x86 ILP32, embedded IoT AMQP clients). Enabling information disclosure or denial of service. Not exploitable on 64-bit systems where sizet is 64-bit. This issue has been patched in version 0.17.0.

— MITRE