CVE-2026-111770: falha de alta gravidade em @modelcontextprotocol server
Model Context Protocol TypeScript SDK: Shared transport or server instances delivered one HTTP client's messages to another
Publicada em
Aviso por e-mail quando ela entrar no KEV, ganhar PoC pública ou subir de nota.
41Vexday Risk Score
Sem sinal de exploração. Ela tem prova de conceito pública.
ssvc Attendcvss 7.7epss 0.4%
da publicação à armano mesmo dia
Publicada no NVD5 de nov.
1ª PoC21 de out.
The Model Context Protocol TypeScript SDK provides TypeScript client and server implementations of the Model Context Protocol. From 2.0.0 until 2.3.0 in @modelcontextprotocol/server, applications that shared one stateless HTTP transport or one McpServer or Server instance among multiple clients could deliver responses and notifications to the wrong client. The affected surface is an MCP server reached over HTTP by multiple clients. The trigger is reuse of one stateless transport or server instance. Messages were associated with a connection using only the JSON-RPC request identifier. SDK clients start request identifiers at zero, so collisions occur in normal operation. Cross-client delivery exposes one client's responses and notifications to another client. The issue requires an HTTP endpoint reachable by more than one client and an application that constructs the server or transport once at startup instead of once per request or session. stdio servers and factory-created per-call servers are not affected. Upgrading causes reused instances to fail and therefore requires an application code change. This issue is fixed in @modelcontextprotocol/server 2.3.0.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:H
PoCs públicas encontradas — 1
githubgithub.com/hahahahahahahahah6/mcp-idprobe★ 0⚠ Recursos públicos, para você avaliar a exposição de sistemas que controla ou está autorizado a testar. Teste apenas com autorização.
CVEs relacionadas — @modelcontextprotocol server
No mesmo produto, das mais perigosas para as menos.
CVE-2026-111768HIGHModel Context Protocol TypeScript SDK: One HTTP request within the default size limit could exhaust server memory during validationEPSS 0.6%CVE-2025-66414HIGHDNS Rebinding Protection Disabled by Default in Model Context Protocol TypeScript SDK for Servers Running on LocalhostEPSS 0.5%CVE-2026-111771MEDIUMModel Context Protocol TypeScript SDK: Server bearer authentication accepted tokens issued for another serviceEPSS 0.5%CVE-2026-111769MEDIUMModel Context Protocol TypeScript SDK: HTTP client transports and OAuth requests followed cross-origin redirects and re-sent custom headers and request bodiesEPSS 0.4%CVE-2026-111767HIGHMCP TypeScript SDK: Experimental tasks were not tied to the session that created themEPSS 0.3%CVE-2026-25536HIGH@modelcontextprotocol/sdk has cross-client data leak via shared server/transport instance reuseEPSS 0.3%
Referências
https://github.com/modelcontextprotocol/typescript-sdk/commit/84804c22e45a662675a198f853b7f00063838a8dhttps://github.com/modelcontextprotocol/typescript-sdk/pull/2918https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/1.32.0https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/@modelcontextprotocol/server@2.3.0https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-jm63-cq47-j5jp