Modelcontextprotocol vulnerabilities
We track 31 vulnerabilities in Modelcontextprotocol products across 14 products. 31 are rated high or critical, and none are known to be exploited. The most recent was published on November 5, 2026.
Latest Modelcontextprotocol vulnerabilities
- 7.7 High severity
typescript-sdk: Concurrent Execution using Shared Resource with Improper Synchronization
The Model Context Protocol TypeScript SDK provides TypeScript client and server implementations of the Model Context Protocol. From 2.0.0 until 2.3.0 in @modelcontextprotocol/server, applications that shared one stateless HTTP transport or one McpServer or Ser
- 7.5 High severity
typescript-sdk: Allocation of Resources Without Limits or Throttling
The Model Context Protocol TypeScript SDK provides TypeScript client and server implementations of the Model Context Protocol. From 1.3.0 until 1.32.0 in @modelcontextprotocol/sdk and from 2.0.0 until 2.3.0 in @modelcontextprotocol/server, HTTP servers did not
- 7.5 High severity
open: Improper Neutralization of Special Elements used in an OS Command
open 7.2.0 before 11.0.0 contains an OS command injection vulnerability that allows attackers to execute PowerShell code by supplying crafted URLs on Windows and WSL. Attackers can embed $(...) subexpressions in URLs, such as OAuth authorization_endpoint value
- 8.6 High severity
typescript-sdk: Authorization Bypass Through User-Controlled Key
MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. From version 1.24.0 to before version 1.32.0, the experimental tasks feature (taskStore) did not check which session created a task. Clients sharing one InMemoryT
- 7.5 High severity
python-sdk: Allocation of Resources Without Limits or Throttling
The Model Context Protocol Python SDK is the official Python SDK for Model Context Protocol servers and clients. In mcp versions before 1.29.1 and from 2.0.0a1 through 2.0.1, the Streamable HTTP session manager, SSE message endpoint, and OAuth authorization-se
- 7.5 High severity
io.modelcontextprotocol.sdk:mcp: Allocation of Resources Without Limits or Throttling
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.modelcontex
- 7.5 High severity
kotlin-sdk: Allocation of Resources Without Limits or Throttling
MCP Kotlin SDK through 0.15.0 contains an uncontrolled memory allocation vulnerability that allows remote clients to exhaust server memory because Application.mcpWebSocket installs Ktor WebSockets without a maxFrameSize limit. Attackers can send small frame he
- 7.5 High severity
typescript-sdk: Insufficient Verification of Data Authenticity
MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. Starting in version 1.12.0 and prior to versions 1.31.0 and 2.2.0, the SDK's OAuth client support let the MCP server a client connected to decide which authorizat
- 7.3 High severity
mcp-server-fetch: Server-Side Request Forgery
A security vulnerability has been detected in modelcontextprotocol mcp-server-fetch and mcp-server-everything up to 2026.6.4. Affected is the function fetch_url of the file mcp_server_fetch/server.py of the component Fetch Tool. The manipulation of the argumen
- 7.5 High severity
rust-sdk: Uncontrolled Resource Consumption
RMCP is an official Rust SDK for the Model Context Protocol. Prior to 2.0.0, the rmcp crate's stateful Streamable HTTP server in crates/rmcp/src/transport/streamable_http_server/tower.rs allows an unauthenticated client to send a well-formed JSON-RPC POST that
- 8.2 High severity
rust-sdk: Insufficient Verification of Data Authenticity
RMCP is an official Rust SDK for the Model Context Protocol. Prior to 2.0.0, the rmcp crate's OAuth implementation in crates/rmcp/src/transport/auth.rs omits the RFC 9728 resource field from ResourceServerMetadata and allows discover_oauth_server_via_resource_
- 7.5 High severity
ruby-sdk: Allocation of Resources Without Limits or Throttling
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 unauthenticat
- 8.3 High severity
ruby-sdk: Improper Access Control
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
- 8.1 High severity
python-sdk: Origin Validation Error
The MCP Python SDK, called mcp on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to 1.28.1, the deprecated mcp.server.websocket.websocket_server transport accepted WebSocket handshakes without applying Host or Origin header validat
- 7.6 High severity
python-sdk: Missing Authorization
The MCP Python SDK, called mcp on PyPI, is a Python implementation of the Model Context Protocol (MCP). From 1.23.0 until 1.27.2, default handlers installed by server.experimental.enable_tasks() for tasks/list, tasks/get, tasks/result, and tasks/cancel operate
- 7.1 High severity
python-sdk: Authorization Bypass Through User-Controlled Key
The MCP Python SDK, called mcp on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to 1.27.2, the SSE and stateful Streamable HTTP transports mcp.server.sse.SseServerTransport and mcp.server.streamable_http_manager.StreamableHTTPSess
- 8.8 High severity
rust-sdk: Origin Validation Error
RMCP is an official Rust SDK for the Model Context Protocol. Prior to version 1.4.0, the rmcp crate's Streamable HTTP server transport (crates/rmcp/src/transport/streamable_http_server/) did not validate the incoming Host header. This allowed a malicious publi
- 8.1 High severity
go-sdk: Initialization of a Resource with an Insecure Default
The Go MCP SDK used Go's standard encoding/json. Prior to version 1.4.0, the Model Context Protocol (MCP) Go SDK does not enable DNS rebinding protection by default for HTTP-based servers. When an HTTP-based MCP server is run on localhost without authenticatio
- 7.5 High severity
go-sdk: Improper Handling of Case Sensitivity
The Go MCP SDK used Go's standard encoding/json.Unmarshal for JSON-RPC and MCP protocol message parsing in versions prior to 1.3.1. Go's standard library performs case-insensitive matching of JSON keys to struct field tags — a field tagged json:"method" would
- 7.1 High severity
typescript-sdk: Concurrent Execution using Shared Resource with Improper Synchronization
MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. From version 1.10.0 to 1.25.3, cross-client response data leak when a single McpServer/Server and transport instance is reused across multiple client connections,
- 9.1 Critical severity
servers: Improper Limitation of a Pathname to a Restricted Directory
In mcp-server-git versions prior to 2025.12.17, when the server is started with the --repository flag to restrict operations to a specific repository path, it did not validate that repo_path arguments in subsequent tool calls were actually within that configur
- 7.1 High severity
servers: Improper Neutralization of Argument Delimiters in a Command
In mcp-server-git versions prior to 2025.12.17, the git_diff and git_checkout functions passed user-controlled arguments directly to git CLI commands without sanitization. Flag-like values (e.g., `--output=/path/to/file` for `git_diff`) would be interpreted as
- 8.8 High severity
servers: Improper Limitation of a Pathname to a Restricted Directory
Model Context Protocol Servers is a collection of reference implementations for the model context protocol (MCP). In mcp-server-git versions prior to 2025.9.25, the git_init tool accepted arbitrary filesystem paths and created Git repositories without validati
- 8.1 High severity
python-sdk: Initialization of a Resource with an Insecure Default
The MCP Python SDK, called `mcp` on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to version 1.23.0, tThe Model Context Protocol (MCP) Python SDK does not enable DNS rebinding protection by default for HTTP-based servers. When an
- 8.1 High severity
typescript-sdk: Initialization of a Resource with an Insecure Default
MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. Prior to 1.24.0, The Model Context Protocol (MCP) TypeScript SDK does not enable DNS rebinding protection by default for HTTP-based servers. When an HTTP-based MC
- 8.6 High severity
inspector: Improper Neutralization of Encoded URI Schemes in a Web Page
The MCP inspector is a developer tool for testing and debugging MCP servers. A cross-site scripting issue was reported in versions of the MCP Inspector local development tool prior to 0.16.6 when connecting to untrusted remote MCP servers with a malicious redi
- 8.7 High severity
python-sdk: Uncaught Exception
The MCP Python SDK, called `mcp` on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to version 1.9.4, a validation error in the MCP SDK can cause an unhandled exception when processing malformed requests, resulting in service unavai
- 8.7 High severity
python-sdk: Uncaught Exception
The MCP Python SDK, called `mcp` on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to version 1.10.0, if a client deliberately triggers an exception after establishing a streamable HTTP session, this can lead to an uncaught ClosedR
- 7.3 High severity
servers: Improper Limitation of a Pathname to a Restricted Directory
Model Context Protocol Servers is a collection of reference implementations for the model context protocol (MCP). Versions of Filesystem prior to 0.6.4 or 2025.7.01 could allow access to unintended files in cases where the prefix matches an allowed directory.
- 7.3 High severity
servers: Improper Link Resolution Before File Access
Model Context Protocol Servers is a collection of reference implementations for the model context protocol (MCP). Versions of Filesystem prior to 0.6.4 or 2025.7.01 could allow access to unintended files via symlinks within allowed directories. Users are advis
- 9.4 Critical severity
inspector: Missing Authentication for Critical Functionality
The MCP inspector is a developer tool for testing and debugging MCP servers. Versions of MCP Inspector below 0.14.1 are vulnerable to remote code execution due to lack of authentication between the Inspector client and proxy, allowing unauthenticated requests