{
 "id": "CVE-2026-51883",
 "description": "The knowledge base creation and document upload interfaces in Langchain-Chatchat 0.3.0;0.3.1 is vulnerable to path traversal. An attacker can inject path traversal sequences (such as `..\\`) into the `knowledge_base_name` parameter to write knowledge base content to arbitrary locations outside the configured knowledge base root directory.",
 "published": "2026-10-01",
 "last_modified": "2026-10-05",
 "vuln_status": "Deferred",
 "cna": "cve@mitre.org",
 "cvss": {
  "version": "3.1",
  "score": 9.1,
  "severity": "CRITICAL",
  "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
  "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
 },
 "cwe": [
  "CWE-22"
 ],
 "products": [
  {
   "vendor": "LangChain",
   "product": "LangChain",
   "versions_affected": null,
   "fixed_in": null,
   "product_id": "langchain"
  }
 ],
 "category": "framework",
 "surface": [
  "path_traversal"
 ],
 "kev": null,
 "fix": {
  "status": "unknown",
  "version": null,
  "url": null
 },
 "references": [
  {
   "url": "https://gist.github.com/Ro1ME/30f5139a2920bf7075299a33eb1690f2",
   "source": "cve@mitre.org",
   "tags": []
  },
  {
   "url": "https://github.com/chatchat-space/Langchain-Chatchat/issues/5467",
   "source": "cve@mitre.org",
   "tags": []
  },
  {
   "url": "https://github.com/chatchat-space/Langchain-Chatchat/issues/5467",
   "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
   "tags": []
  }
 ],
 "related_agents": [
  "langchain-langchain",
  "langchain-langchain-deep-agents"
 ],
 "related_incidents": [],
 "match": {
  "tests": [
   "A:cpe"
  ],
  "terms": [
   "langchain:langchain:langchain"
  ]
 },
 "status": "candidate",
 "note": null,
 "reviewer": null,
 "checked_on": null,
 "retrieved_on": "2026-10-25"
}