CVE-2026-30352: Leonvanzyl Autocoder RCE Vulnerability

CVE-2026-30352 Overview

A remote code execution (RCE) vulnerability has been identified in the /devserver/start endpoint of leonvanzyl autocoder at commit 79d02a. This command injection flaw allows unauthenticated attackers to execute arbitrary code on the target system by supplying a maliciously crafted command parameter to the vulnerable endpoint.

Critical Impact
This vulnerability enables remote attackers to achieve full system compromise through unauthenticated command injection, potentially leading to complete loss of confidentiality, integrity, and availability of affected systems.

Affected Products

leonvanzyl autocoder (commit 79d02a and potentially other versions)

Discovery Timeline

2026-04-27 - CVE-2026-30352 published to NVD
2026-04-27 - Last updated in NVD database

Technical Details for CVE-2026-30352

Vulnerability Analysis

This vulnerability falls under CWE-77 (Command Injection), where the application constructs a command using externally-influenced input but fails to properly neutralize special elements that could modify the intended command. The /devserver/start endpoint accepts a command parameter that is passed to an underlying system shell without adequate sanitization or validation.

The network-accessible nature of this vulnerability is particularly concerning as it requires no authentication or user interaction to exploit. An attacker can remotely trigger arbitrary command execution simply by sending a specially crafted HTTP request to the vulnerable endpoint.

Root Cause

The root cause of this vulnerability is improper input validation in the /devserver/start endpoint. The application accepts user-controlled input for the command parameter and passes it directly to a system command execution function without sanitizing shell metacharacters or implementing proper input validation. This allows attackers to inject additional commands using shell operators such as semicolons, pipes, or command substitution syntax.

Attack Vector

The attack is carried out over the network by sending an HTTP request to the /devserver/start endpoint with a maliciously crafted command parameter. The attacker can append arbitrary shell commands to the expected input, which are then executed by the underlying operating system with the privileges of the application process.

The vulnerability mechanism involves the application failing to validate or sanitize the command parameter before passing it to shell execution functions. Attackers can leverage shell metacharacters to break out of the intended command context and execute arbitrary commands. For detailed technical information, see the GitHub Gist Code Snippet and the GitHub AutoCoder Repository.

Detection Methods for CVE-2026-30352

Indicators of Compromise

Unusual HTTP requests to the /devserver/start endpoint containing shell metacharacters (;, |, $(), backticks)
Unexpected child processes spawned by the autocoder application
Network connections originating from the autocoder process to external IP addresses
Suspicious command execution patterns in system logs associated with the web application process

Detection Strategies

Monitor HTTP access logs for requests to /devserver/start with suspicious command parameter values
Implement Web Application Firewall (WAF) rules to detect and block command injection patterns
Configure intrusion detection systems to alert on shell metacharacter sequences in web traffic
Review application logs for anomalous command parameter inputs

Monitoring Recommendations

Enable verbose logging for the autocoder application to capture all incoming requests
Implement real-time monitoring for process creation events from the application context
Set up alerts for any outbound network connections initiated by the autocoder process
Monitor file system changes in directories accessible by the application

How to Mitigate CVE-2026-30352

Immediate Actions Required

Disable or restrict access to the /devserver/start endpoint immediately
Implement network-level access controls to limit exposure of the autocoder application
Review system logs for any signs of exploitation
Isolate affected systems from production networks until patched

Patch Information

As of the last update on 2026-04-27, no official patch has been released for this vulnerability. Users should monitor the GitHub AutoCoder Repository for security updates and patches. Consider implementing the workarounds below until an official fix is available.

Workarounds

Implement strict input validation for the command parameter, using allowlists for permitted characters
Deploy a reverse proxy or WAF with rules to block requests containing shell metacharacters
Restrict network access to the autocoder application to trusted IP addresses only
Run the application in a sandboxed environment with minimal system privileges

bash

# Example: Restrict access to /devserver/start endpoint using nginx
location /devserver/start {
    # Deny all external access
    deny all;
    # Or limit to specific trusted IPs
    # allow 192.168.1.0/24;
    # deny all;
}