{"id":"CVE-2026-106119","aliases":["EUVD-2026-93771","GHSA-m6rx-h84q-8r95"],"status":"published","title":"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.","severity":{"version":"4.0","score":6,"vector":"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","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00463,"percentile":0.40634,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-943"],"published":"2026-10-06T18:01:24Z","modified":"2026-10-28T02:30:21Z","fixes":[{"ecosystem":"npm","package":"@langchain/mongodb","fixed_in":["1.3.1"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"@langchain/mongodb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"1.3.0"},{"fixed":"1.3.1"}]}]},{"source":"osv","ecosystem":"npm","package":"@langchain/mongodb","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.3.1"}]}]}],"products":[{"vendor":"@feathersjs","product":"mongodb"},{"vendor":"@langchain","product":"mongodb"},{"vendor":"langchain-ai","product":"langchainjs"}],"references":[{"url":"https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-m6rx-h84q-8r95","tags":["x_refsource_CONFIRM","advisory","web"]},{"url":"https://github.com/langchain-ai/langchainjs/pull/11672","tags":["x_refsource_MISC","fix","web"]},{"url":"https://github.com/langchain-ai/langchainjs/commit/946e3d856ff1f8ce7f7b9374c83f680a6ada79af","tags":["x_refsource_MISC","fix","web"]},{"url":"https://github.com/langchain-ai/langchainjs/releases/tag/@langchain/mongodb@1.3.1","tags":["x_refsource_MISC","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-106119","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-m6rx-h84q-8r95"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/106xxx/CVE-2026-106119.json","tags":["advisory"]},{"url":"https://github.com/langchain-ai/langchainjs","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-106119","title":"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.","status":"published","published":"2026-10-06T18:01:24.262Z","modified":"2026-10-06T19:45:43.997Z","cvss":[{"version":"4.0","score":6,"vector":"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","level":"medium","assessor":"cna"}],"cwes":["CWE-943"],"updated_at":"2026-11-02T14:20:04.156238Z"}],"euvd":[{"id":"EUVD-2026-93771","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.","status":"published","published":"2026-10-06T18:01:24Z","modified":"2026-10-06T19:45:43Z","cvss":[{"version":"4.0","score":6,"vector":"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","level":"medium"}],"updated_at":"2026-11-02T17:27:36.701921Z"}],"ghsa":[{"id":"GHSA-m6rx-h84q-8r95","title":"LangChain: MongoDBChatMessageHistory query injection can allow cross-session access","description":"## Impact\n\n`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.\n\nApplications 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.\n\nApplications that derive the session identifier from an authenticated, server-controlled value and enforce its type are not affected by this path.\n\n## Patches\n\nThe issue is fixed in `@langchain/mongodb` version **1.3.1**.\n\nUsers 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.\n\n## Workarounds\n\nIf 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.\n\nUpgrading remains the recommended remediation.","status":"published","published":"2026-10-08T17:52:22Z","modified":"2026-10-08T17:52:24Z","cvss":[{"version":"4.0","score":6,"vector":"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","level":"medium"}],"cwes":["CWE-943"],"updated_at":"2026-11-02T14:41:30.097746Z"}],"nvd":[{"id":"CVE-2026-106119","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.","status":"published","published":"2026-10-06T19:17:42.8Z","modified":"2026-10-06T20:17:17.82Z","cvss":[{"version":"4.0","score":6,"vector":"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/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","level":"medium","assessor":"secondary"}],"cwes":["CWE-943"],"updated_at":"2026-11-02T14:12:54.486849Z"}],"osv":[{"id":"CVE-2026-106119","title":"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.","status":"published","published":"2026-10-06T18:01:24.262Z","modified":"2026-10-28T02:30:21.560884675Z","cvss":[{"version":"4.0","score":6,"vector":"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","level":"medium"}],"cwes":["CWE-943"],"updated_at":"2026-11-02T15:44:54.583213Z"},{"id":"GHSA-m6rx-h84q-8r95","title":"LangChain: MongoDBChatMessageHistory query injection can allow cross-session access","description":"## Impact\n\n`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.\n\nApplications 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.\n\nApplications that derive the session identifier from an authenticated, server-controlled value and enforce its type are not affected by this path.\n\n## Patches\n\nThe issue is fixed in `@langchain/mongodb` version **1.3.1**.\n\nUsers 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.\n\n## Workarounds\n\nIf 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.\n\nUpgrading remains the recommended remediation.","status":"published","published":"2026-10-08T17:52:22Z","modified":"2026-10-08T18:00:08.902627724Z","cvss":[{"version":"4.0","score":6,"vector":"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","level":"medium"}],"cwes":["CWE-943"],"updated_at":"2026-11-02T15:46:51.463834Z"}]}}