CVE-2026-1083957.5HighCWE-770

CVE-2026-108395: Model Context Protocol Java SDK HTTP server transports allow memory exhaustion through unbounded request bodies

modelcontextprotocol · io.modelcontextprotocol.sdk:mcp

Affected: modelcontextprotocol io.modelcontextprotocol.sdk:mcp · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.6%probability of exploitation in the next 30 days

49th percentile

050100

Higher than 49% of scored CVEs

7.5HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

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.

Affected products2

From the CVE record. A product or version that is not listed is unknown, not unaffected.

modelcontextprotocol · io.modelcontextprotocol.sdk:mcp>= 0.8.0, < 0.13.0
modelcontextprotocol · io.modelcontextprotocol.sdk:mcp-core>= 0.13.0, < 0.18.4; >= 1.0.0, < 1.1.4; >= 2.0.0-M1, < 2.0.1

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Allocation Without Limits · Denial of Service
Vendor: modelcontextprotocol
Published: October 2026
Band: Unlikely (under 1%), October 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-108395 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.