CVE-2026-63119

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StdioTransport and MCP::Client::Stdio in the mcp gem use IOgets without a byte limit, allowing a peer that sends data without a newline to exhaust process memory. This...

PT-2026-65889

Name of the Vulnerable Software and Affected Versions mcp versions prior to 0.23.0 Description The MCP::Server::Transports::StdioTransport and MCP::Client::Stdio components in the mcp gem use the IOgets function without a byte limit. This allows a peer that sends data without a newline character ...

CVE-2026-63119: Uncontrolled Resource Consumption

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StdioTransport and MCP::Client::Stdio in the mcp gem use IOgets without a byte limit, allowing a peer that sends data without a newline to exhaust process memory. This...

LangBot: Authenticated RCE Via MCP Configuration

SummaryAny authenticated user can achieve arbitrary command execution on the LangBot servers through changing the MCP Server Configuration by added an "STDIO" MCP with an arbitrary command. DetailsThe repository uses StdioServerParameters which is based on Anthropic's modelcontextprotocol open...

PYSEC-2026-3473 LangBot: Authenticated RCE Via MCP Configuration

Summary Any authenticated user can achieve arbitrary command execution on the LangBot servers through changing the MCP Server Configuration by added an "STDIO" MCP with an arbitrary command. Details The repository uses StdioServerParameters which is based on Anthropic's modelcontextprotocol open...

Exploit for CVE-2026-30623

mcpshield !Python 3.10+https://img.shields.io/badge/python...

Allocation of Resources Without Limits or Throttling

Overview mcp is a The official Ruby SDK for Model Context Protocol servers and clients Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling in the stdio transports lib/mcp/server/transports/stdiotransport.rb and lib/mcp/client/stdio.rb, which ca...

CVE-2026-30618: Improper Control of Generation of Code

xszyou Fay 4.3.1 contains a remote code execution vulnerability in its MCP STDIO server management and command execution handling. A remote attacker can access the publicly exposed MCP management interface and configure an MCP STDIO server with attacker-controlled commands and parameters, resulti...

CVE-2026-54149

MaxKB is an open-source AI assistant for enterprise. Prior to 2.10.0-lts, MaxKB tool import functionality in apps/tools/serializers/tool.py and MCP referencing mode in apps/application/chatpipeline/step/chatstep/impl/basechatstep.py do not consistently validate MCP transport type, allowing an...

CVE-2026-54149 MaxKB MCP tool import validation bypass allows post-authentication remote code execution

MaxKB is an open-source AI assistant for enterprise. Prior to 2.10.0-lts, MaxKB tool import functionality in apps/tools/serializers/tool.py and MCP referencing mode in apps/application/chatpipeline/step/chatstep/impl/basechatstep.py do not consistently validate MCP transport type, allowing an...

Neo4j Cypher MCP server is vulnerable to DNS rebinding

ImpactDNS rebinding vulnerability in Neo4j Cypher MCP server allows malicious websites to bypass Same-Origin Policy protections and execute unauthorised tool invocations against locally running Neo4j MCP instances. The attack relies on the user being enticed to visit a malicious website and spend...

Unbounded line buffer in stdio transports leads to memory exhaustion (DoS)

Summary The stdio transports in MCP::Server::Transports::StdioTransport and MCP::Client::Stdio read newline-delimited JSON-RPC frames using IOgets with no limit argument. CRuby's IOgets with no limit reads from the current position until the next separator \n with no upper bound on the returned...

PYSEC-2026-559 Upsonic: remote code execution vulnerability in its MCP server/task creation functionality

Upsonic 0.71.6 contains a remote code execution vulnerability in its MCP server/task creation functionality. The application allows users to define MCP tasks with arbitrary command and args values. Although an allowlist exists, certain allowed commands npm, npx accept argument flags that enable...

PT-2026-53628

Upsonic 0.71.6 contains a remote code execution vulnerability in its MCP server/task creation functionality. The application allows users to define MCP tasks with arbitrary command and args values. Although an allowlist exists, certain allowed commands npm, npx accept argument flags that enable...

CVE-2026-4339: Server-Side Request Forgery (SSRF)

Mattermost versions 10.11.x = 10.11.18, 11.6.x = 11.6.3, 11.5.x = 11.5.6 fail to validate attachment URLs against internal or private IP ranges in the Mattermost Agents plugin MCP server which allows an attacker with access to the MCP server in stdio mode to perform server-side request forgery SS...

Missing Authentication for Critical Function

Overview @n8n/mcp-browser is a Browser automation MCP tools built on Playwright, WebDriver BiDi, and safaridriver Affected versions of this package are vulnerable to Missing Authentication for Critical Function through the MCP server’s HTTP request handling. An attacker can take over a user’s...

CVE-2026-30616

Jaaz 1.0.30 contains a remote code execution vulnerability in its MCP STDIO command execution handling. A remote attacker can send crafted network requests to the network-accessible Jaaz application, causing attacker-controlled commands to be executed on the server. Successful exploitation result...

CVE-2026-6130

A flaw has been found in chatboxai chatbox up to 1.20.0. This impacts the function StdioClientTransport of the file src/main/mcp/ipc-stdio-transport.ts of the component Model Context Protocol Server Management System. Executing a manipulation of the argument args/env can lead to os command...

CVE-2026-40933

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to 3.1.0, due to unsafe serialization of stdio commands in the MCP adapter, an authenticated attacker can add an MCP stdio server with an arbitrary command, achieving command execution. The vulnerabilit...

CVE-2026-44450 Lumiverse: RCE via MCP stdio argument injection

Lumiverse is a full-featured AI chat application. Prior to 0.9.7, the MCP server creation endpoint validates the command field against an allowlist of binary names but forwards the args array to the child process without any validation. Every binary on the allowlist accepts an inline-code executi...