CVE-2026-48121: langchain-ai langgraphjs

Vulnerability summary

CVE-2026-48121 is a medium (CVSS 6.7) vulnerability in langchain-ai langgraphjs. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 27.7% of scored vulnerabilities.

Timeline

1. 04-08-2026
   PublishedVulnerability first disclosed.
2. 04-08-2026
   Last modifiedVulnerability information updated.

Description

@langchain/langgraph-checkpoint-mongodb provides a LangGraph.js CheckpointSaver implementation that uses MongoDB for storage. Versions 1.3.0 and below are vulnerable to NoSQL injection: checkpoint identifiers (thread_id, checkpoint_ns, checkpoint_id) from config.configurable are passed into MongoDB find() queries in MongoDBSaver.getTuple() without type enforcement. If an attacker supplies an object payload (such as MongoDB operators $gt or $ne) instead of a string, it can be interpreted as a query operator, bypassing thread scoping and leaking checkpoints, including pending writes, across tenants. Applications are at risk if they forward untrusted input into config.configurable without coercing it to strings or validating it against a schema, particularly in multi-tenant or user-isolated setups. Apps that only use server-issued, string-typed identifiers with schema validation rejecting non-string fields are not affected. This issue has been fixed in version 1.3.1.

• CWE-943Improper Neutralization of Special Elements in Data Query LogicThe product generates a query intended to access or manipulate data in a data store such as a database, but it does not neutralize or incorrectly neutralizes special elements that can modify the intended logic of the query.