detecting-insecure-deserialization
Installation
SKILL.md
Detecting Insecure Deserialization
Overview
Insecure deserialization (CWE-502, OWASP A08:2021) is the highest-
severity injection class in many language stacks because it directly
maps to RCE. Pickle, Java serialization, PHP unserialize, and
BinaryFormatter all execute object-construction code during
deserialization. If that code includes __reduce__ /
readObject / __wakeup / OnDeserialization callbacks that
the attacker controls, the deserialization step IS code execution.
Most legitimate use cases have safer alternatives (JSON for data, YAML with safe-load, Protocol Buffers, Avro). The remaining cases need explicit type allow-lists and HMAC-signed payloads.