LangChain: MongoDBChatMessageHistory query injection can allow cross-session access

{
  "id": "692cf2efe89c329958221f76a902d7f0486eaa5d10930d51cb22a4e097e256a9",
  "url": "https://osv.dev/vulnerability/GHSA-m6rx-h84q-8r95",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "LangChain: MongoDBChatMessageHistory query injection can allow cross-session access",
    "summary": "## Impact `MongoDBChatMessageHistory` did not enforce the documented string type for session identifiers at runtime. In affected applications, a structured session identifier could be interpreted as a MongoDB query condition rather than as a literal identifier. Applications are affected when they pass untrusted session identifier input to `MongoDBChatMessageHistory` and store multiple users’ histories in the same collection. An attacker who can invoke chat-history operations may be able to read, modify, or delete another user’s stored conversation. Applications that derive the session identifier from an authenticated, server-controlled value and enforce its type are not affected by this path. ## Patches The issue is fixed in `@langchain/mongodb` version **1.3.1**. Users of affected versions should upgrade to version 1.3.1 or later. The patched version validates session identifiers at runtime and ensures they are compared as literal values in MongoDB queries. ## Workarounds If an immediate upgrade is not possible, applications must reject session identifiers that are not non-empty strings. Session identifiers should be derived from an authenticated, server-controlled value and must not be passed directly from an untrusted request field. Upgrading remains the recommended remediation.",
    "evidence": "osv:GHSA-m6rx-h84q-8r95",
    "products": [
      {
        "name": {
          "value": "@langchain/mongodb",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1.3.1",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "GHSA-m6rx-h84q-8r95",
      "aliases": [
        "CVE-2026-106119",
        "GHSA-m6rx-h84q-8r95"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "1.3.1"
                }
              ]
            }
          ],
          "package": {
            "name": "@langchain/mongodb",
            "purl": "pkg:npm/%40langchain/mongodb",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-m6rx-h84q-8r95/GHSA-m6rx-h84q-8r95.json",
            "last_known_affected_version_range": "<= 1.3.0"
          }
        }
      ],
      "modified": "2026-10-08T18:00:08.902627724Z",
      "provider": "osv",
      "references": [
        "https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-m6rx-h84q-8r95",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-106119",
        "https://github.com/langchain-ai/langchainjs/pull/11672",
        "https://github.com/langchain-ai/langchainjs/commit/946e3d856ff1f8ce7f7b9374c83f680a6ada79af",
        "https://github.com/langchain-ai/langchainjs",
        "https://github.com/langchain-ai/langchainjs/releases/tag/@langchain/mongodb@1.3.1"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-943"
        ],
        "severity": "MODERATE",
        "github_reviewed": true,
        "nvd_published_at": "2026-10-06T19:17:42Z",
        "github_reviewed_at": "2026-10-08T17:52:22Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-106119",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 104433,
  "published_at": "2026-10-08T17:52:22+00:00"
}