CVE-2026-59279

The MCP Streamable HTTP server transport WebFlux and WebMvc variants does not place any limit on the number of sessions it retains, and by default does not require clients to be authenticated. As a result, a remote attacker can cause the server to accumulate an unbounded number of sessions over...

CVE-2026-59279

Spring AI 2.0.0 is affected by a Denial of Service vulnerability in the MCP Streamable HTTP server transport (both WebFlux and WebMvc variants). The transport does not impose any limit on the number of sessions it retains and, by default, does not require client authentication. A remote unauthent...

CVE-2026-59279 Unbounded persistent session allocation via repeated initialize requests

The MCP Streamable HTTP server transport WebFlux and WebMvc variants does not place any limit on the number of sessions it retains, and by default does not require clients to be authenticated. As a result, a remote attacker can cause the server to accumulate an unbounded number of sessions over...

EUVD-2026-50498

MCP Ruby SDK: Unbounded session retention in StreamableHTTPTransport allows memory exhaustion via initialize flood...

CVE-2026-67432

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem reads and parses an entire JSON-RPC POST body without a size limit, allowing an unauthenticated remote attacker to exhaust process...

CVE-2026-67432

CVE-2026-67432 affects the MCP Ruby SDK before version 0.23.0. The vulnerability exists in MCP::Server::Transports::StreamableHTTPTransport of the mcp gem, which reads and parses an entire JSON-RPC POST body without a size limit, allowing an unauthenticated remote attacker to exhaust memory on th...

CVE-2026-67432 MCP Ruby SDK: Unbounded JSON-RPC request body causes uncontrolled memory allocation in StreamableHTTPTransport

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem reads and parses an entire JSON-RPC POST body without a size limit, allowing an unauthenticated remote attacker to exhaust process...

CVE-2026-67432

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem reads and parses an entire JSON-RPC POST body without a size limit, allowing an unauthenticated remote attacker to exhaust process...

CVE-2026-67432 MCP Ruby SDK: Unbounded JSON-RPC request body causes uncontrolled memory allocation in StreamableHTTPTransport

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem reads and parses an entire JSON-RPC POST body without a size limit, allowing an unauthenticated remote attacker to exhaust process...

CVE-2026-67431 MCP Ruby SDK: Ruby SSE Session Poisoning

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem does not bind a session ID to a session owner, allowing an attacker with a stolen session ID to send tools/call requests that...

CVE-2026-67431

The CVE affects the MCP Ruby SDK (Model Context Protocol) prior to version 0.23.0. In MCP::Server::Transports::StreamableHTTPTransport, the session ID is not bound to a session owner, allowing a stolen session ID to cause requests (tools/call) to execute in the victim’s session. This is fixed in ...

CVE-2026-67430

CVE-2026-67430 affects the MCP Ruby SDK (mcp gem) prior to 0.23.0. The vulnerability is in MCP::Server::Transports::StreamableHTTPTransport, which does not expire sessions by default, allowing repeated initialize requests to retain unbounded ServerSession objects and cause memory exhaustion. The ...

CVE-2026-67430 MCP Ruby SDK: Unbounded session retention in StreamableHTTPTransport allows memory exhaustion via initialize flood

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem does not expire sessions by default, so repeated initialize requests retain unbounded ServerSession objects and can exhaust proces...

CVE-2026-67430 MCP Ruby SDK: Unbounded session retention in StreamableHTTPTransport allows memory exhaustion via initialize flood

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem does not expire sessions by default, so repeated initialize requests retain unbounded ServerSession objects and can exhaust proces...

CVE-2026-63118 MCP Ruby SDK: Streamable HTTP transport lacks DNS-rebinding (Host/Origin) protection

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem does not validate the HTTP Host or Origin request headers, which allows a malicious browser page to use DNS rebinding to reach a...

PT-2026-65899

Name of the Vulnerable Software and Affected Versions mcp versions prior to 0.23.0 Description The MCP::Server::Transports::StreamableHTTPTransport component in the mcp gem reads and parses an entire JSON-RPC POST body without enforcing a size limit. This allows an unauthenticated remote attacker...

CVE-2026-16498

The terraform-mcp-server before version 1.1.0 is vulnerable to a cross-tenant credential reuse issue in the streamable-HTTP stateless transport mode that may allow one user's Terraform token to be used to execute tool calls on behalf of subsequent users. This vulnerability, CVE-2026-16498, is fix...

CVE-2026-16496

The terraform-mcp-server before version 1.1.0 is vulnerable to an authorization bypass in the streamable-HTTP stateful transport mode that may allow a user who obtains another user's MCP session ID to have their tool calls executed using that user's Terraform credentials. This vulnerability,...

CVE-2026-16498

The terraform-mcp-server package is affected up to version 1.0.x; in the streamable-HTTP stateless transport mode, a cross-tenant credential reuse vulnerability allows one user’s Terraform token to be used to execute tool calls for subsequent users. Root cause: improper isolation between tenants ...

CVE-2026-16498 terraform-mcp-server vulnerable to cross-tenant credential reuse in streamable-HTTP stateless mode

The terraform-mcp-server before version 1.1.0 is vulnerable to a cross-tenant credential reuse issue in the streamable-HTTP stateless transport mode that may allow one user's Terraform token to be used to execute tool calls on behalf of subsequent users. This vulnerability, CVE-2026-16498, is fix...