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

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 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...

EUVD-2026-49934

The terraform-mcp-server before version 1.1.0 is vulnerable to a server-side request forgery issue in the streamable-HTTP transport that may allow an unauthenticated remote client to redirect the server's Terraform API requests, and the server-side authorization token, to an attacker-controlled...

CVE-2026-16496: Session Fixation

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: Exposure of Data Element to Wrong Session

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-2026-14869: Server-Side Request Forgery (SSRF)

The terraform-mcp-server before version 1.1.0 is vulnerable to a server-side request forgery issue in the streamable-HTTP transport that may allow an unauthenticated remote client to redirect the server's Terraform API requests, and the server-side authorization token, to an attacker-controlled...

Open WebUI's chat completion API allows tool restrictions to be bypassed

SummaryOpen WebUI v0.6.43 contains a vulnerability in its chat completion API, which allows attackers to bypass tool restrictions, potentially enabling unauthorized actions or access. DetailsIn the chatcompletion API, the parameters toolids and toolservers are supplied by the user. These paramete...

CVE-2026-59822: Improper Authentication

LiteLLM is a proxy server AI Gateway to call LLM APIs in OpenAI or native format. Prior to 1.84.0, LiteLLM's MCP Streamable HTTP endpoint allowed an unauthenticated attacker to use a fabricated Authorization header to trigger an OAuth2 passthrough fallback path that replaced failed LiteLLM key...

Model Context Protocol (MCP) Python SDK does not enable DNS rebinding protection by default

DescriptionThe Model Context Protocol MCP Python SDK does not enable DNS rebinding protection by default for HTTP-based servers. When an HTTP-based MCP server is run on localhost without authentication using FastMCP with streamable HTTP or SSE transport, and has not configured...

Unbounded JSON-RPC request body causes uncontrolled memory allocation in StreamableHTTPTransport

Summary An unauthenticated remote attacker can force any MCP Ruby SDK server using MCP::Server::Transports::StreamableHTTPTransport to allocate gigabytes of memory by sending a single oversized JSON-RPC POST. The transport reads the entire HTTP body into a Ruby String and parses it with...

excel-mcp-server has a Path Traversal issue

SummaryA path traversal vulnerability exists in excel-mcp-server versions up to and including 0.1.7. When running in SSE or Streamable-HTTP transport mode the documented way to use this server remotely, an unauthenticated attacker on the network can read, write, and overwrite arbitrary files on t...

NPM: Streamable HTTP mode exposes LINE Desktop read/send tools without MCP authentication

NPM: Streamable HTTP mode exposes LINE Desktop read/send tools without MCP authentication vulnerability discovered by ? in WordPress Npm line-desktop-mcp versions = 1.1.1...

CVE-2026-49357 Streamable HTTP mode exposes LINE Desktop read/send tools without MCP authentication

Line Desktop MCP is a project that, while unaffiliated with the official line-bot-mcp-server, allows users to directly operate the LINE Desktop application on Windows or Mac via MCP. line-desktop-mcp supports a --http-mode Streamable HTTP transport for use with clients such as n8n. In this mode t...

OpenClaw: MCP Streamable HTTP redirects could forward configured custom headers to another origin

Summary OpenClaw supports remote MCP Streamable HTTP servers with operator-configured custom headers. In affected releases, those headers could be forwarded when the MCP endpoint responded with a cross-origin redirect. This issue is limited to configured MCP Streamable HTTP servers that use custo...

Information Exposure

Overview openclaw is a 🦞 OpenClaw — Personal AI Assistant Affected versions of this package are vulnerable to Information Exposure via the MCP Streamable HTTP process when custom headers are configured and the MCP endpoint responds with a cross-origin redirect. An attacker can obtain sensitive...

GHSA-X7CF-6GP3-Q5F8 Duplicate Advisory: MCP Streamable HTTP redirects could forward configured custom headers to another origin

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-rjxq-qqhf-8hwh. This link is maintained to preserve external references. Original Description OpenClaw before 2026.5.12 contains an information disclosure vulnerability in streamable-http MCP servers that forwar...

CVE-2026-53840 OpenClaw < 2026.5.12 - Custom Header Leakage via MCP Streamable HTTP Cross-Origin Redirects

OpenClaw before 2026.5.12 contains an information disclosure vulnerability in streamable-http MCP servers that forwards operator-configured custom headers during cross-origin redirects. Attackers controlling or compromising an MCP endpoint can redirect requests to exfiltrate sensitive headers lik...