MCP TypeScript SDK: One HTTP request within the default size limit could exhaust server memory during validation

影響: npm:@modelcontextprotocol/sdk >= 1.3.0, < 1.32.0 → 1.32.0, npm:@modelcontextprotocol/server >= 2.0.0, < 2.3.0 → 2.3.0

In affected versions, servers put no limit on how many array elements and object keys they validated in one request. One HTTP request within the default 4 MiB size limit could exhaust the server's memory, and the process aborted with JavaScript heap out of memory. No credentials are needed, unless you authenticate requests before they reach the SDK. Am I affected? Yes, if clients you do not fully trust can reach your server over HTTP. The risk is highest for McpServer tools whose input…

Read on GitHub Advisory Database

On 10/21/2026, 05:06 AM, GitHub Advisory Database published "MCP TypeScript SDK: One HTTP request within the default size limit could exhaust server memory during validation" (type: Advisory). Severity is "High" (high). Related technologies: JavaScript / Node.js. CVE: CVE-2026-111768.