Unsafe deserialization

Why this agent matters

Deserializing attacker-controlled data with pickle, Java serialization or PHP unserialize can lead straight to remote code execution. The 2015 Apache Commons Collections gadget chain showed how far one library could reach.

The same call is perfectly safe on trusted, internal data, so the deciding question is the trust boundary. This agent answers it and tells you when a safe loader is already in use.

What it checks

• pickle.loads, marshal, non-safe yaml.load
• Java ObjectInputStream and PHP unserialize
• Type-resolving JSON or XML deserializers
• Whether the input crosses a trust boundary

When it marks a finding as a likely false positive

• The data source is trusted and internal
• A safe loader such as yaml.safe_load is used

The fix it suggests

• A safe format such as JSON with a schema
• yaml.safe_load or allow-listed types
• Signed data when objects must round-trip

Scope and limits

This agent validates findings reported by Semgrep, Gitleaks and Trivy; it doesn't hunt for new bugs on its own. A finding reaches it when its CWE or rule/path keywords match this vulnerability class. It sees only the minimal code around the finding, with secrets redacted, and returns a verdict with a confidence score, a plain-English explanation and a suggested patch.

Common questions

Related agents

• SQL injection — Decides whether attacker-controlled input actually reaches a SQL or NoSQL query unparameterized.
• Cross-site scripting (XSS) — Checks whether untrusted data is rendered into HTML or JavaScript without contextual encoding.
• Server-side request forgery (SSRF) — Checks whether a server-side request can be pointed at a host the attacker chooses.

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