Memory Flooding Vulnerability in Model Context Protocol SDK by Model Context Protocol
CVE-2026-108395
What is CVE-2026-108395?
The Model Context Protocol Java SDK, utilized for servers and clients, contains a vulnerability that allows an unauthenticated remote client to exploit the Servlet-based SSE, Streamable HTTP, and Stateless server transports. This occurs when an excessively large HTTP request body is accepted into memory without a defined maximum size, leading to potential heap exhaustion. If not mitigated, this could render the Java process unavailable. The affected versions have been updated to enforce request size limits effectively, with fixes provided in versions 0.18.4, 1.1.4, and 2.0.1.
Affected Version(s)
io.modelcontextprotocol.sdk:mcp >= 0.8.0, < 0.13.0
io.modelcontextprotocol.sdk:mcp-core >= 0.13.0, < 0.18.4 < 0.13.0, 0.18.4
io.modelcontextprotocol.sdk:mcp-core >= 1.0.0, < 1.1.4 < 1.0.0, 1.1.4