Critical · published December 24, 2025
🔥 A sneaky serialization injection in LangChain could turn user data into a recipe for disaster! Think of it like a restaurant serving dishes with secret ingredients hidden in the menu. If the chef isn’t careful about what goes into the pot, a seemingly innocent order could lead to a culinary catastrophe! An attacker could manipulate serialized data to insert unauthorized objects into your application, potentially gaining control over it. This could lead to exploits like data leakage or even complete system compromise, with devastating consequences for your users and their data!
Think of it like a restaurant serving dishes with secret ingredients hidden in the menu. If the chef isn’t careful about what goes into the pot, a seemingly innocent order could lead to a culinary catastrophe! This vulnerability arises from LangChain's dumps() and dumpd() functions failing to escape dictionaries containing 'lc' keys when serializing free-form dictionaries. Consequently, user data may be wrongly treated as legitimate LangChain objects upon deserialization, allowing for unauthorized functionality execution.
An attacker could manipulate serialized data to insert unauthorized objects into your application, potentially gaining control over it. This could lead to exploits like data leakage or even complete system compromise, with devastating consequences for your users and their data! Upgrade to LangChain versions 0.3.81 or 1.2.5 to patch this vulnerability immediately. Additionally, consider auditing your serialization processes to ensure that user data is adequately validated and sanitized. Implement strict controls around data handling to mitigate similar risks in the future. You've got this! Just follow these steps, and you'll fortify your application against this sneaky injection! 🛡️
| Product | Versions | Fixed in |
|---|---|---|
| langchain/langchain_core | < 0.3.81 | 0.3.81 |
| langchain/langchain_core | ≥ 1.0.0, < 1.2.5 | 1.2.5 |