2025-12 · 2025-Q4
LangChain "LangGrinch" Serialization Injection
Layer tags: not yet tagged.
Target
LangChain Core (before 0.3.81)
Impact
Secret exfiltration and potential RCE via LLM-influenced metadata containing reserved 'lc' key
Root Cause
dumps()/dumpd() did not escape user-controlled dicts with reserved serialization marker