{
 "public_id": "AIR-2026-0137",
 "incident_id": "2026-06-langchain-file-search-path-traversal",
 "date_disclosed": "2026-06-12",
 "date_occurred": null,
 "title": "CVE-2026-55443: path traversal and sandbox escape in LangChain's file-search middleware and loaders",
 "class": "responsible_disclosure",
 "attack_surface": "agent_framework",
 "initial_vector": "agent_supplied_glob_pattern_or_symlink",
 "agent_capability_abused": [
  "file_search",
  "file_read",
  "glob_expansion"
 ],
 "target_product": "langchain, langchain-anthropic",
 "target_vendor": "LangChain Inc.",
 "autonomy_level": "semi_autonomous",
 "impact_realized": false,
 "impact_type": [
  "arbitrary_file_read",
  "sandbox_escape"
 ],
 "blast_radius": "langchain <= 1.3.8 and langchain-anthropic <= 1.4.5 using the file-search middleware",
 "cve": [
  "CVE-2026-55443"
 ],
 "taxonomy": {
  "owasp_asi": [
   "ASI05",
   "ASI03"
  ],
  "mitre_atlas": [],
  "labels": [
   "path_traversal",
   "symlink_attack",
   "glob_bypass",
   "scope_violation",
   "file_tool"
  ]
 },
 "defense_present": "starting-directory validation, but not on glob patterns or symlink targets, and prefix checks without segment boundaries",
 "defense_bypassed": true,
 "fix_shipped": "langchain 1.3.9, langchain-anthropic 1.4.6",
 "primary_sources": [
  "https://github.com/advisories/GHSA-gr75-jv2w-4656"
 ],
 "verified_quote": "LangChain: Path traversal and sandbox escape in LangChain file-search middleware and loaders",
 "confidence": "high",
 "notes": "GHSA-gr75-jv2w-4656, CVSS 5.1 Moderate. Same defect family as Anthropic's Filesystem MCP EscapeRoute (prefix matching without a path-segment boundary, plus unfollowed symlink checks) - included as evidence that this bug class recurs across agent file tools rather than for its severity.",
 "risk_category": "security_fraud",
 "risk_secondary": [],
 "risk_subcategory": "Remote Code Execution & Sandbox Escape",
 "risk_sub_secondary": [],
 "ai_entity": "generative",
 "agency": "agent_acted",
 "agency_debatable": true,
 "agency_reason": "the agent-supplied glob escaped the sandbox and read arbitrary files",
 "vector_family": "other",
 "vector_detail": "agent_supplied_glob_pattern_or_symlink",
 "guardrail_kind": [
  "unknown"
 ],
 "guardrail_outcome": "silent",
 "xrefs": {
  "aiid": [],
  "atlas": [],
  "cve": [
   "CVE-2026-55443"
  ],
  "ghsa": []
 },
 "primary_asi": "ASI05",
 "agent_framework": "langchain",
 "model_provider": "anthropic",
 "model_name": "",
 "detection_mechanism": "unknown",
 "tool_access": "unknown",
 "financial_loss_band": "unknown",
 "eai_category": "privilege_escalation",
 "eai_domain": "access_control_and_permissions",
 "eai_secondary": [],
 "eai_reason": "subcategory: Remote Code Execution & Sandbox Escape",
 "asi_curated": [],
 "asi_scope": "in_scope",
 "asi_provenance": "rule",
 "asi_reason": "ASI05 (impact=code_exec); ASI03 (signal=identity)",
 "submitted_by": "EAI Internal"
}