CVE-2026-39313
MCP-Framework: Unbounded memory allocation in readRequestBody allows denial of service via HTTP transport
Vexday Risk Score
21Low
SSVC decision (CISA)
Track
No exploitation signal → monitor
CVSS 8.7EPSS 0.5%KEV nãoPoC —Nuclei —Metasploit —Patch —
Lifecycle
16 Apr 2026Published on NVD
Recommendation: Monitor — no exploitation signal at the moment.
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.
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
Affected products
QuantGeekDev · mcp-frameworkWant to know if your infrastructure is exposed to this?
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