CVE-2026-2824 Overview
A command injection vulnerability has been discovered in the Comfast CF-E7 router firmware version 2.6.0.9. This flaw affects the sub_441CF4 function within the /cgi-bin/mbox-config?method=SET§ion=ping_config endpoint of the webmggnt component. Remote attackers with low privileges can exploit this vulnerability by manipulating the destination argument to execute arbitrary commands on the affected device. The exploit has been publicly disclosed, and the vendor was contacted but did not respond.
Critical Impact
Remote attackers can achieve command execution on vulnerable Comfast CF-E7 routers by exploiting improper input validation in the ping configuration functionality, potentially leading to full device compromise.
Affected Products
- Comfast CF-E7 Firmware version 2.6.0.9
- Comfast CF-E7 hardware devices
Discovery Timeline
- 2026-02-20 - CVE CVE-2026-2824 published to NVD
- 2026-02-20 - Last updated in NVD database
Technical Details for CVE-2026-2824
Vulnerability Analysis
This vulnerability is classified as Command Injection (CWE-77) and Injection (CWE-74). The flaw resides in the web management interface of Comfast CF-E7 routers running firmware version 2.6.0.9. The vulnerable endpoint /cgi-bin/mbox-config handles ping configuration requests through the method=SET§ion=ping_config parameters. The sub_441CF4 function fails to properly sanitize user-supplied input in the destination argument before passing it to system commands.
An authenticated attacker with network access can craft malicious requests containing shell metacharacters or command sequences in the destination parameter. When the router processes these requests, the injected commands are executed with the privileges of the web server process, typically root on embedded devices.
Root Cause
The root cause of this vulnerability is insufficient input validation and sanitization in the sub_441CF4 function. The ping configuration functionality accepts a destination parameter that is intended to specify a target IP address or hostname for network diagnostics. However, the function does not adequately filter or escape shell metacharacters before incorporating user input into system command execution. This allows attackers to break out of the intended command context and inject arbitrary commands.
Attack Vector
The attack can be performed remotely over the network by an authenticated user. The attacker must have valid credentials or access to the router's web management interface. By sending a crafted HTTP request to the /cgi-bin/mbox-config endpoint with a malicious destination parameter value containing command injection payloads (such as shell metacharacters like ;, |, $(), or backticks), the attacker can execute arbitrary system commands on the router.
The vulnerability is exploitable through standard HTTP requests to the web management interface, making it accessible to any attacker with network connectivity to the device and valid authentication credentials.
Detection Methods for CVE-2026-2824
Indicators of Compromise
- Unusual HTTP requests to /cgi-bin/mbox-config with suspicious characters in the destination parameter
- Unexpected processes spawned by the web server process on the router
- Abnormal outbound network connections from the router to external IP addresses
- Modified system files or configurations on the affected device
Detection Strategies
- Monitor HTTP access logs for requests to /cgi-bin/mbox-config containing shell metacharacters (;, |, &, $, backticks) in query parameters
- Implement Web Application Firewall (WAF) rules to detect command injection patterns in requests targeting the ping configuration endpoint
- Deploy network intrusion detection signatures for command injection attempts against Comfast devices
- Review authentication logs for suspicious login activity to the web management interface
Monitoring Recommendations
- Enable detailed logging on the router's web management interface if supported
- Monitor network traffic for unusual patterns originating from the router
- Set up alerts for any HTTP requests to the vulnerable endpoint containing non-alphanumeric characters in the destination field
- Implement network segmentation to isolate IoT devices and limit potential lateral movement
How to Mitigate CVE-2026-2824
Immediate Actions Required
- Restrict network access to the router's web management interface using firewall rules or access control lists
- Disable remote administration if not required for operations
- Change default credentials and use strong, unique passwords for the web interface
- Isolate the affected device on a separate network segment until a patch is available
Patch Information
No official patch is currently available from Comfast. The vendor was contacted about this vulnerability but did not respond. Users should monitor the VulDB entry and the GitHub CVE Report for updates. Consider replacing vulnerable devices with supported alternatives if no patch is forthcoming.
Workarounds
- Implement strict network access controls to limit who can reach the management interface
- Use a VPN for remote management access instead of exposing the web interface directly
- Deploy an upstream firewall or reverse proxy to filter malicious requests before they reach the device
- Consider replacing the affected device with a router from a vendor with active security support
# Example: Restrict access to management interface using iptables on upstream firewall
# Allow management access only from trusted admin IP
iptables -A FORWARD -d <router_ip> -p tcp --dport 80 -s <admin_ip> -j ACCEPT
iptables -A FORWARD -d <router_ip> -p tcp --dport 80 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
