CVE-2026-39313 — MCP-Framework: Unbounded memory allocation in readRequestBody allows denial of service via HTTP transport
mcp-framework is a framework for building Model Context Protocol (MCP) servers. In versions 0.2.21 and below, the readRequestBody() function in the HTTP transport concatenates r…
Published: 2026-04-16 · CVSS: 8.7 · CVSS 4.0
mcp-framework is a framework for building Model Context Protocol (MCP) servers. In versions 0.2.21 and below, the readRequestBody() function in the HTTP transport concatenates request body chunks into a string with no size limit. Although a maxMessageSize configuration value exists, it is never enforced in readRequestBody(). A remote unauthenticated attacker can crash any mcp-framework HTTP server by sending a single large POST request to /mcp, causing memory exhaustion and denial of service. This issue has been fixed in version 0.2.22.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7