CVE-2026-108395
Model Context Protocol Java SDK HTTP server transports allow memory exhaustion through unbounded request bodies
- State
- Published
- Severity
- 7.5 High
- Published
- Oct 14, 2026
- Updated
- Oct 14, 2026
- Reserved
- Oct 9, 2026
Description
The Model Context Protocol Java SDK is the official Java SDK for Model Context Protocol servers and clients. From version 0.8.0 through 0.12.0 in the io.modelcontextprotocol.sdk:mcp artifact, from 0.13.0 through 0.18.3 and 1.0.0 through 1.1.3 in io.modelcontextprotocol.sdk:mcp-core, and from mcp-core 2.0.0-M1 through 2.0.0, the Servlet-based SSE, Streamable HTTP, and Stateless server transports read an HTTP request body into memory without enforcing a maximum size. An unauthenticated remote client able to reach an affected transport can stream an arbitrarily large POST body, including with chunked transfer encoding, until the Java process exhausts its heap and becomes unavailable. Authentication, Origin or Host validation, or an upstream request-size limit can reject the request before the vulnerable read. The maintained mcp-core lines are fixed in versions 0.18.4, 1.1.4, and 2.0.1.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.5 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | GitHub_M |
Weaknesses
- CWE-770 Allocation of Resources Without Limits or Throttling
Affected Products
| Product | Versions |
|---|---|
io.modelcontextprotocol.sdk:mcpmodelcontextprotocol |
|
io.modelcontextprotocol.sdk:mcp-coremodelcontextprotocol |
|
References
- https://github.com/modelcontextprotocol/java-sdk/security/advisories/GHSA-4x8c-5vv7-973f
- https://github.com/modelcontextprotocol/java-sdk/commit/1499df22c7023aa257223143a5dcf5b1db7ef80d
- https://github.com/modelcontextprotocol/java-sdk/commit/6a41dedaa0625551582d8247e5a4d78eae1131b2
- https://github.com/modelcontextprotocol/java-sdk/commit/8c0fdd1b1f76adba3ce7945d29f73fa2ddc66598
- https://github.com/modelcontextprotocol/java-sdk/commit/9e4d5fa827b6ba69457f5fd93573184789528efa
- https://github.com/modelcontextprotocol/java-sdk/releases/tag/v0.18.4
- https://github.com/modelcontextprotocol/java-sdk/releases/tag/v1.1.4
- https://github.com/modelcontextprotocol/java-sdk/releases/tag/v2.0.1
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.