CVE-2026-106119
LangChain: MongoDBChatMessageHistory query injection can allow cross-session access
Description
LangChain is a framework for building LLM-powered applications. Prior to 1.3.1, MongoDBChatMessageHistory does not enforce the documented string type for an untrusted structured session identifier at runtime, allowing the identifier to be interpreted as a MongoDB query condition rather than as a literal value when multiple users' histories are stored in a shared MongoDB collection. An attacker able to invoke chat-history operations can read, modify, or delete another user's stored conversation. Applications using authenticated, server-controlled string identifiers are not affected. This issue is fixed in version 1.3.1.
INFO
Published Date :
Oct. 6, 2026, 7:17 p.m.
Last Modified :
Oct. 6, 2026, 8:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update LangChain to version 1.3.1 or later.
- Ensure session identifiers are string types.
- Validate input for session identifiers.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-106119.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-106119 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-106119
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-106119 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-106119 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Oct. 06, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-106119', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-10-06T19:45:00.727020Z'} -
New CVE Received by [email protected]
Oct. 06, 2026
Action Type Old Value New Value Added Description LangChain is a framework for building LLM-powered applications. Prior to 1.3.1, MongoDBChatMessageHistory does not enforce the documented string type for an untrusted structured session identifier at runtime, allowing the identifier to be interpreted as a MongoDB query condition rather than as a literal value when multiple users' histories are stored in a shared MongoDB collection. An attacker able to invoke chat-history operations can read, modify, or delete another user's stored conversation. Applications using authenticated, server-controlled string identifiers are not affected. This issue is fixed in version 1.3.1. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-943 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/106xxx/CVE-2026-106119.json">CVE-2026-106119</a> Added Reference https://github.com/langchain-ai/langchainjs/commit/946e3d856ff1f8ce7f7b9374c83f680a6ada79af Added Reference https://github.com/langchain-ai/langchainjs/pull/11672 Added Reference https://github.com/langchain-ai/langchainjs/releases/tag/@langchain/[email protected] Added Reference https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-m6rx-h84q-8r95