CVE-2024-0401 Overview
CVE-2024-0401 is a command injection vulnerability affecting ASUS routers that support custom OpenVPN profiles. An authenticated remote attacker can execute arbitrary operating system commands by uploading a crafted .ovpn profile. The flaw is tracked under CWE-78, OS Command Injection. Known affected models include ASUS ExpertWiFi, RT-AX55, RT-AX58U, RT-AC67U, RT-AC68R, RT-AC68U, RT-AX86, RT-AC86U, RT-AX88U, and RT-AX3000. Successful exploitation yields code execution on the router with full impact to confidentiality, integrity, and availability.
Critical Impact
Authenticated attackers can achieve remote code execution on affected ASUS routers by uploading a malicious OpenVPN profile, compromising the network gateway and any traffic transiting it.
Affected Products
- ASUS ExpertWiFi, RT-AX55, RT-AX58U, RT-AX86, RT-AX88U, RT-AX3000
- ASUS RT-AC67U, RT-AC68R, RT-AC68U, RT-AC86U
- Any ASUS router firmware version supporting custom OpenVPN client profile import
Discovery Timeline
- 2024-05-20 - CVE-2024-0401 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-0401
Vulnerability Analysis
The vulnerability resides in the OpenVPN client profile handling logic on affected ASUS routers. The web management interface accepts a user-supplied .ovpn configuration file and passes directive values into shell contexts without proper sanitization. OpenVPN configuration directives can reference external scripts and helper binaries, which the parser invokes during profile activation. When these directive values contain shell metacharacters, the router executes attacker-controlled commands as the OpenVPN parent process, typically running with elevated privileges on the embedded Linux system.
Exploitation requires authenticated access to the router administrative interface. Once inside, an attacker uploads a crafted profile and triggers the client to consume it, achieving code execution on the underlying operating system.
Root Cause
The root cause is improper neutralization of special elements used in an operating system command [CWE-78]. Profile fields are concatenated into command strings executed by the router's shell without escaping or allow-listing. Because OpenVPN natively supports options that reference shell-invoked helpers, the parser expands untrusted input into executable command context.
Attack Vector
The attack is network-based and requires high privileges, meaning valid administrator credentials for the router web interface. No user interaction is required after authentication. An attacker submits a malicious OpenVPN profile through the VPN client configuration endpoint, then activates the profile to trigger command execution. See the VulnCheck ASUS VPN RCE Advisory for additional technical context.
Detection Methods for CVE-2024-0401
Indicators of Compromise
- Unexpected .ovpn profile uploads in router administrative logs, particularly containing shell metacharacters such as backticks, $(), semicolons, or pipes inside directive values
- Unusual outbound connections from the router itself to unknown IP addresses following VPN client configuration changes
- New or modified processes spawned by the OpenVPN client daemon that do not correspond to normal VPN operation
Detection Strategies
- Inspect stored OpenVPN profiles for directives referencing external commands such as up, down, route-up, or tls-verify with suspicious arguments
- Monitor router administrative login sessions for anomalous authenticated activity, particularly configuration changes to VPN settings from unfamiliar source addresses
- Correlate firmware integrity checks against known-good ASUS release hashes to identify tampering post-exploitation
Monitoring Recommendations
- Forward router syslog and administrative audit events to a centralized logging platform for retention and correlation
- Alert on any process execution originating from the OpenVPN client outside expected binaries such as openvpn and its documented helpers
- Track outbound DNS and HTTP requests initiated by the router management plane for signs of command-and-control activity
How to Mitigate CVE-2024-0401
Immediate Actions Required
- Apply the latest ASUS firmware for the specific router model from the official ASUS support portal
- Rotate router administrator credentials and disable any shared or default accounts
- Restrict web administrative interface access to trusted internal networks only, disabling WAN-side administration
Patch Information
ASUS has released firmware updates addressing CVE-2024-0401 for the affected router families. Consult the VulnCheck ASUS VPN RCE Advisory and the ASUS product support page for the specific model to obtain the fixed firmware version. Apply updates through the router web interface or ASUS firmware update utility.
Workarounds
- Disable the OpenVPN client feature if custom profile import is not required for business operations
- Restrict administrative access to the router to a management VLAN or specific source IP addresses using built-in access control lists
- Enforce multi-factor authentication where supported and use strong, unique administrator passwords to limit the likelihood of authenticated exploitation
# Configuration example: restrict administrative access and disable remote management
# From the ASUS router web UI (Administration > System):
# Enable Web Access from WAN: No
# Enable SSH: LAN only
# Enable Telnet: No
# Then rotate credentials:
# Router Login Name / Password: <set strong unique values>
# If OpenVPN client is not required, disable it under:
# VPN > VPN Client > Remove all imported .ovpn profiles
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
