CVE-2026-108395
Description
A flaw was found in the Model Context Protocol (MCP) Java SDK, which can lead to a Denial of Service (DoS). The server transports read incoming HTTP request bodies directly into memory without enforcing a maximum size limit. An unauthenticated remote attacker can exploit this vulnerability by sending an arbitrarily large HTTP request, exhausting available memory and rendering the service unavailable.
Statement
This vulnerability is rated as Important severity for Red Hat because an unauthenticated remote attacker can trigger unbounded memory allocation without prior privileges, leading to host Java Virtual Machine heap exhaustion. In typical deployments exposing Model Context Protocol HTTP server transports, streaming arbitrarily large POST bodies can result in a denial of service across the entire application runtime. Environments where endpoints are isolated behind authenticated reverse proxies, constrained by upstream size limits, or restricted to trusted internal networks face significantly lower risk.
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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