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Fencer Intel
medium 6.7

CVE-2026-48121 json

@langchain/langgraph-checkpoint-mongodb: NoSQL parameter injection in MongoDBSaver allows cross-tenant state access

published 4mo ago modified 18d ago also GHSA-98xf-r82g-9mhx , EUVD-2026-52793

cvss
6.7
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits
0
none known

Summary

@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.

Patch / fix

  • npm @langchain/langgraph-checkpoint-mongodb 1.3.1

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
3mo ago

Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 6.7 CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
GitHub 3.1 6.7 CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

Affected packages

ecosystem package affected fixed in
npm @langchain/langgraph-checkpoint-mongodb
<1.3.1
1.3.1

Affected products

  • langchain-ai langgraphjs

Classification

Weakness
  • CWE-943 Improper Neutralization of Special Elements in Data Query Logic

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.