Two ArangoDB Bugs, One Root Cause

Picture this: No password needed. There's no API token. Nothing. With one well-placed request, an attacker achieves an unauthenticated RCE in your CI/CD pipeline, taking full control of your build secrets and cloud identities.

That's not an imaginary scenario. It's a real security bug we found in CircleCI's MCP server. Critically severe, fully unauthenticated remote code execution. It's a worst-case scenario and it's all too real.

Expected CVSS3.1 designation: 10.0, Critical (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H)
CVE has been requested and is pending assignment.

How It Works

The CircleCI MCP server can run as a shared, network-reachable service, allowing a whole team - or their AI agents - to access one instance. In this mode, the server carries the organization's API token to complete its tasks. To keep things safe and block sketchy browser-based attacks, a check is run on the request's Host and Origin headers.

• Automatic validation before and after changes
• Instant revert if something goes wrong
• Full transparency into every action

export function isOriginAllowed(origin: string | undefined, allowed: Set<string>): boolean {
  // Non-browser clients (mcp-remote, curl) send no Origin – allow them.
  if (!origin?.trim()) return true;
  return allowed.has(origin.trim().toLowerCase());
}
export function isHostAllowed(host: string | undefined, allowed: Set<string>): boolean {
  return !!host?.trim() && allowed.has(host.trim().toLowerCase());
}

What the Attack Looks Like

The AI Arms Race

AI accelerates reconnaissance, exploit chaining, and lateral movement beyond human speed. Detection-first models cannot keep up.

• Automatic hardening and drift control
  • Configurations are enforced continuously, not just audited
    • Configurations are enforced continuously, not just audited
• Real-time compliance
  • CIS, NIST, ISO, and internal frameworks enforced live

And now, the loop is closing completely with the addition of vulnerability management, patch management, application control, and network scanning.

About the Author

Omri Dar

Lead Vulnerability Researcher

Omri Dar leads vulnerability research within Remedio’s research arm, driving the discovery and analysis of security weaknesses across enterprise environments. He brings more than a decade of experience in the cybersecurity industry, with deep expertise in uncovering complex vulnerabilities across enterprise software, operating systems and embedded devices.