{
 "id": "AIR-2026-0806",
 "slug": "cve-2026-52869-mcp-python-sdk-http-transports-fail-to-verify",
 "title": "CVE-2026-52869: MCP Python SDK HTTP transports fail to verify authenticated principal",
 "summary": "The SSE and Streamable HTTP server transports in the MCP Python SDK route incoming session requests solely by session identifier without verifying the authenticated principal. Attackers who guess a session ID can send JSON-RPC messages across that session.",
 "type": "attack_on_ai",
 "categories": [
  "infra_vuln"
 ],
 "severity": 2,
 "targets": [
  "framework_or_tooling"
 ],
 "products": [
  "MCP Python SDK"
 ],
 "incident_date": "2026-07-16",
 "incident_date_precision": "day",
 "first_reported": "2026-07-15",
 "sources": [
  {
   "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-52869",
   "publisher": "NVD",
   "title": "CVE-2026-52869: The MCP Python SDK, called mcp on PyPI, is a Python implementation of the Model Context Protocol (MCP).",
   "published_at": "2026-07-15"
  },
  {
   "url": "https://github.com/advisories/GHSA-jpw9-pfvf-9f58",
   "publisher": "GitHub Advisory Database",
   "title": "CVE-2026-52869: MCP Python SDK: HTTP transports serve session requests without verifying the authenticated principal",
   "published_at": "2026-07-16"
  }
 ],
 "source_count": 2,
 "confidence": 0.95,
 "status": "published",
 "origin": "seed_ghsa",
 "tags": [
  "CVE-2026-52869",
  "mcp",
  "authentication"
 ],
 "created_at": "2026-10-18T07:00:14.101Z",
 "updated_at": "2026-10-18T10:04:21.885Z"
}