CVE-2026-111770

waiting for further signals

GHSA-jm63-cq47-j5jp ↗

no check availablenot proven exploitable

awaiting cvepublic pockev

npm:@modelcontextprotocol/server >= 2.0.0, < 2.3.0

fixed in 2.3.0

CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

ETK-2026-1687, permanent identifier

pkg:npm/@modelcontextprotocol/server

cvss7.7cna vendorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:H

5d 14h 29msince last run

29mAI analysis

timeline

0 = cve.org, not yet published

trigger signal −5.7dwaiting for further signals−5.6d

−4d

−2d

description

@modelcontextprotocol/server versions 2.0.0 through 2.2.0 can send HTTP responses or notifications to the wrong client when multiple clients share a server instance or stateless transport. An attacker able to access such a shared endpoint may receive another client's messages when request identifiers overlap.

mitigation

Upgrade @modelcontextprotocol/server to 2.3.0 or later. Create separate server and transport instances per request or session, or use a handler factory that creates a new server for each call.

fixed in 2.3.0

check

exploit

automation

–

auth required

EPSS

–

agent run time

29m

cve.org record, t = 0

not published yet

Δ to public poc

–

Δ to kev

–

outcome

No artifact: an exploit or check was attempted but could not be produced at this moment.

source signals

Public signals that triggered or updated the pipeline. These are inputs for the deltas above.

2026-10-15 13:10Z
ghsa: trigger signal, started the run
https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-jm63-cq47-j5jp

this entry in the feed

GET /api/v1/feed/CVE-2026-111770

{
  "etk_id": "ETK-2026-1687",
  "cve_id": "CVE-2026-111770",
  "display_id": "CVE-2026-111770",
  "ghsa_id": "GHSA-jm63-cq47-j5jp",
  "euvd_id": null,
  "status": "published",
  "anchor_state": "awaiting_cve",
  "title": "Cross-client message mix-up in @modelcontextprotocol/server",
  "summary": "@modelcontextprotocol/server versions 2.0.0 through 2.2.0 can send HTTP responses or notifications to the wrong client when multiple clients share a server instance or stateless transport. An attacker able to access such a shared endpoint may receive another client's messages when request identifiers overlap.",
  "mitigation": "Upgrade @modelcontextprotocol/server to 2.3.0 or later. Create separate server and transport instances per request or session, or use a handler factory that creates a new server for each call.",
  "vendor": "npm",
  "product": "npm:@modelcontextprotocol/server",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 2.0.0, < 2.3.0"
      ],
      "ecosystem": "npm",
      "fixed_versions": [
        "2.3.0"
      ],
      "package_name": "@modelcontextprotocol/server",
      "purl": "pkg:npm/@modelcontextprotocol/server"
    }
  ],
  "cwes": [
    362
  ],
  "cvss_score": 7.7,
  "cvss_src": "cna_vendor",
  "cvss_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:H",
  "epss_score": null,
  "epss_percentile": null,
  "epss_asof": null,
  "automation": "deterministic",
  "check": false,
  "check_confidence_basis": null,
  "exploit": false,
  "pipeline_minutes": 28.681296133333333,
  "t0_at": null,
  "signals": {
    "trigger_signal": {
      "at": "2026-10-15T13:10:24+00:00",
      "days": -5.653087668715278,
      "is_lower_bound": true,
      "measured_at": "2026-10-21T04:50:50.796349+00:00",
      "url": "https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-jm63-cq47-j5jp"
    }
  }
}

published 2026-10-15 14:49Z
last change 2026-10-21 04:45Z

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