CVE-2026–10692: When a Search Feature Can Take Down Your AI Coding Tool

When you use an AI-powered coding assistant that can search through your codebase, you probably assume it's safe. But a recently published security vulnerability — CVE-2026–10692 — shows that even a simple search feature can become a weapon in the wrong hands.

Let's break it down in plain English.

What Is code-index-mcp?

code-index-mcp is an open-source tool built by developer johnhuang316. It acts as a server that helps AI assistants (like those running on the Model Context Protocol, or MCP) search, index, and understand your code. Think of it as giving your AI assistant the ability to read and search your entire codebase intelligently.

What Went Wrong?

The vulnerability lives inside a feature called search_code_advanced, specifically in a function named is_safe_regex_pattern. This function is supposed to check whether a regular expression (regex) — a special pattern used to search text — is safe to run.

The problem? It doesn't do that job well enough.

A malicious user can craft a specially designed regex input that causes the program to work exponentially harder than normal — chewing through CPU resources and grinding the server to a halt. This type of attack is called a ReDoS (Regular Expression Denial of Service).

The Simple Analogy

Imagine asking someone to find a specific word in a book. Normally, they scan page by page — quick and easy. Now imagine giving them a riddle so confusing that they have to re-read every sentence thousands of times before deciding the word isn't there. That's what a ReDoS attack does to a computer.

How Serious Is It?

This vulnerability is rated Medium severity (CVSS score: 5.3 out of 10). Here's what that means in practice:

• Anyone with a basic account on a system using this tool can trigger the attack remotely — no special privileges needed beyond being a logged-in user.
• No data is stolen. This isn't about leaking passwords or source code. The attack is purely about availability — making the service slow or unresponsive.
• A public exploit already exists. The attack method has been publicly disclosed on GitHub, which means it's not theoretical — someone could use it today.

Who Is Affected?

All versions of code-index-mcp from 2.0 up to and including 2.14.0 are vulnerable. That covers a wide range of deployments, especially since many developers tend to stay on stable versions without updating frequently.

The Fix

The good news: a patch is already available. Version 2.14.1 addresses the issue entirely. The fix was applied in commit 25bc02f on the official GitHub repository.

If you're running code-index-mcp, upgrade to v2.14.1 immediately.

You can find the patched release here: 👉 https://github.com/johnhuang316/code-index-mcp/releases/tag/v2.14.1

Why Should Developers Care?

AI coding tools are becoming a core part of daily development workflows. As these tools grow in popularity, they also become attractive targets. Vulnerabilities like CVE-2026–10692 are a reminder that security must be part of the design — not an afterthought.

Regex validation is a notoriously tricky area. Even well-intentioned safety checks can be bypassed if the underlying logic doesn't account for catastrophic backtracking. Libraries like Google's RE2 are designed to prevent this class of problem entirely.

Key Takeaways

• CVE-2026–10692 is a ReDoS vulnerability in the code-index-mcp tool, affecting versions 2.0 through 2.14.0.
• An attacker can remotely send a crafted regex to overload CPU resources and cause a denial of service.
• The fix is simple: update to version 2.14.1.
• Credit goes to security researcher skywings for discovering and reporting this issue.

Stay safe, keep your dependencies updated, and remember: in security, the smallest function can open the biggest door.