Vulnerability · Published Apr 16, 2026 · Assigned by GitHub_M
CVE-2026-39313MCP-Framework: Unbounded memory allocation in readRequestBody allows denial of service via HTTP transport
High 8.7
In plain English
A high-severity resource allocation without limits in mcp-framework from QuantGeekDev. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | mcp-framework | 0.2.22 | GHSA-353c-v8x9-v7c3 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| QuantGeekDev | mcp-framework | < 0.2.22 |
Weakness: CWE-770 · 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