LangChain MongoDB has NoSQL Operator Injection in MongoDBSaver.list() leading to cross-tenant data exposure
A NoSQL injection issue exists in the langgraph-checkpoint-mongodb and langgraph-store-mongodb libraries. MongoDBSaver.list() and MongoDBStore.search() methods accept a filter parameter that is incorporated into MongoDB queries without sufficient validation. Because MongoDB query operator keys (those prefixed with $) are not rejected during filter construction, a caller with control of the filter input can embed MongoDB query operators directly into the query.