CVE-2026-108395 json
Model Context Protocol Java SDK HTTP server transports allow memory exhaustion through unbounded request bodies
published 26d ago modified 24d ago also EUVD-2026-101503
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 49%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- github.com/modelcontextprotocol/java-sdk@1499df2 commit
- github.com/modelcontextprotocol/java-sdk@6a41ded commit
- github.com/modelcontextprotocol/java-sdk@8c0fdd1 commit
- github.com/modelcontextprotocol/java-sdk@9e4d5fa commit
- github.com/modelcontextprotocol/java-sdk/releases/tag/v0.18.4 release
- github.com/modelcontextprotocol/java-sdk/releases/tag/v1.1.4 release
- github.com/modelcontextprotocol/java-sdk/releases/tag/v2.0.1 release
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red hat product security vex CVE-2026-108395 updated cvss 7.5
io.modelcontextprotocol.sdk/mcp: io.modelcontextprotocol.sdk/mcp-core: Model Context Protocol Java SDK: Denial of Service via unbounded HTTP request body
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Red Hat All currently supported Red Hat productsnot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 26d ago
Exploit prediction
0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
- modelcontextprotocol io.modelcontextprotocol.sdk:mcp
- modelcontextprotocol io.modelcontextprotocol.sdk:mcp-core
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
- github.com /modelcontextprotocol/java-sdk/commit/1499df22c7023aa257223143a5dcf5b1db7ef80d
- github.com /modelcontextprotocol/java-sdk/commit/6a41dedaa0625551582d8247e5a4d78eae1131b2
- github.com /modelcontextprotocol/java-sdk/commit/8c0fdd1b1f76adba3ce7945d29f73fa2ddc66598
- github.com /modelcontextprotocol/java-sdk/commit/9e4d5fa827b6ba69457f5fd93573184789528efa
- github.com /modelcontextprotocol/java-sdk/security/advisories/GHSA-4x8c-5vv7-973f
- github.com /modelcontextprotocol/java-sdk/releases/tag/v0.18.4
- github.com /modelcontextprotocol/java-sdk/releases/tag/v1.1.4
- github.com /modelcontextprotocol/java-sdk/releases/tag/v2.0.1
Sources
- CVE List CVE-2026-108395
- NVD CVE-2026-108395
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