CVE-2026-54522

MessagePack for Ruby is an implementation of the MessagePack binary serialization format. Prior to 1.8.2, MessagePack::Bufferclear in ext/msgpack/buffer.c leaves rmemlast, rmemend, and rmemowner stale after msgpackbuffershiftchunk returns an rmem page to the shared pool, allowing a subsequent...

CVE-2026-54522

MessagePack for Ruby is an implementation of the MessagePack binary serialization format. Prior to 1.8.2, MessagePack::Bufferclear in ext/msgpack/buffer.c leaves rmemlast, rmemend, and rmemowner stale after msgpackbuffershiftchunk returns an rmem page to the shared pool, allowing a subsequent...

PT-2026-66528

Name of the Vulnerable Software and Affected Versions MessagePack for Ruby versions prior to 1.8.2 Description A use-after-free issue exists in the MessagePack::Bufferclear function within ext/msgpack/buffer.c. When this function is called, it returns memory pages to a shared pool but fails to...