CVE-2024-49368 Overview
CVE-2024-49368 is a command injection vulnerability in Nginx UI, a web-based user interface for managing the Nginx web server. Prior to version 2.0.0-beta.36, the application fails to properly validate user input when configuring logrotate functionality. The unsanitized input is passed directly to exec.Command, enabling attackers to execute arbitrary commands on the underlying system with the privileges of the Nginx UI process.
Critical Impact
Remote attackers can achieve arbitrary command execution on servers running vulnerable Nginx UI installations, potentially leading to complete system compromise, data exfiltration, and lateral movement within the network.
Affected Products
- Nginx UI versions prior to 2.0.0-beta.36
- Nginx UI 2.0.0-beta1 through 2.0.0-beta35 (including all patch releases)
- All 1.x versions of Nginx UI
Discovery Timeline
- October 21, 2024 - CVE-2024-49368 published to NVD
- November 6, 2024 - Last updated in NVD database
Technical Details for CVE-2024-49368
Vulnerability Analysis
This vulnerability represents a classic command injection flaw resulting from improper input validation. Nginx UI provides a web interface that allows administrators to configure various Nginx-related functionality, including log rotation settings. When processing logrotate configuration requests, the application constructs shell commands by directly concatenating user-supplied input into command strings.
The vulnerability is particularly dangerous because Nginx UI typically runs with elevated privileges to manage the Nginx web server. Successful exploitation grants attackers the ability to execute arbitrary system commands with those same privileges, potentially allowing them to install backdoors, modify system configurations, access sensitive data, or pivot to other systems on the network.
The high EPSS score of 57.71% at the 98th percentile indicates a significant probability of exploitation in the wild, making immediate patching essential for organizations running affected versions.
Root Cause
The root cause is improper input validation (CWE-20) in the logrotate configuration handler. The application accepts user input through the web interface and passes it directly to Go's exec.Command function without sanitization or validation. This allows attackers to inject shell metacharacters and additional commands that get executed by the system shell.
Proper input validation should include:
- Allowlisting acceptable characters for configuration values
- Escaping or rejecting shell metacharacters
- Using parameterized command execution rather than string concatenation
Attack Vector
The attack is network-accessible and requires no authentication or user interaction based on the vulnerability characteristics. An attacker with network access to the Nginx UI web interface can craft malicious requests containing shell commands embedded within logrotate configuration parameters.
The exploitation flow typically involves:
- Attacker identifies a Nginx UI instance accessible over the network
- Attacker accesses the logrotate configuration functionality
- Attacker injects shell commands into configuration fields (e.g., using command separators like ;, &&, or backticks)
- The application passes the malicious input to exec.Command
- The injected commands execute with the privileges of the Nginx UI process
For detailed technical information, refer to the GitHub Security Advisory GHSA-66m6-27r9-77vm.
Detection Methods for CVE-2024-49368
Indicators of Compromise
- Unusual process spawning from the Nginx UI application process, particularly shells or command interpreters
- Unexpected network connections initiated by the Nginx UI service
- Modified or newly created files in system directories that should not be touched by Nginx UI
- Anomalous entries in application logs containing shell metacharacters or command sequences
Detection Strategies
- Monitor web application logs for requests to logrotate configuration endpoints containing suspicious characters such as ;, |, &&, ||, backticks, or $()
- Deploy network intrusion detection rules to identify exploitation attempts targeting Nginx UI logrotate functionality
- Use endpoint detection and response (EDR) solutions to alert on unexpected command execution chains originating from web server processes
- Implement file integrity monitoring on critical system files and directories
Monitoring Recommendations
- Enable verbose logging for the Nginx UI application to capture all configuration change requests
- Monitor process execution trees for the Nginx UI process to detect anomalous child process creation
- Set up alerts for any shell or scripting interpreter execution spawned by the Nginx UI service
- Review authentication logs for unauthorized access attempts to the Nginx UI interface
How to Mitigate CVE-2024-49368
Immediate Actions Required
- Upgrade Nginx UI to version 2.0.0-beta.36 or later immediately
- If immediate upgrade is not possible, restrict network access to the Nginx UI interface using firewall rules
- Review server logs for signs of exploitation or unauthorized access
- Conduct a security assessment of systems running vulnerable Nginx UI versions to check for compromise
Patch Information
The vulnerability is fixed in Nginx UI version 2.0.0-beta.36. The fix implements proper input validation for logrotate configuration parameters, preventing command injection attacks. Administrators should upgrade to the patched version as soon as possible.
Upgrade resources:
Workarounds
- Restrict access to the Nginx UI web interface to trusted IP addresses only using network-level controls
- Place Nginx UI behind a VPN or bastion host to limit exposure
- Implement web application firewall (WAF) rules to filter requests containing shell metacharacters
- Disable or restrict access to logrotate configuration functionality if not required
# Example: Restrict Nginx UI access using iptables
# Allow only management network to access Nginx UI (default port 9000)
iptables -A INPUT -p tcp --dport 9000 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 9000 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
