HIGHCVE-2026-39313Published Modified CNA GitHub_M
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 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.
Metrics
- CVSS v4.0
- 8.7
- Severity
- HIGH
- Fixed in
- —
- Affected Products
- 1
Affected packages
- QuantGeekDev / mcp-framework< 0.2.22
CVSS Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N