CVE-2024-0920 Overview
CVE-2024-0920 is a command injection vulnerability in the TRENDnet TEW-822DRE wireless range extender running firmware version 1.03B02. The flaw resides in the POST request handler for /admin_ping.htm, where the ipv4_ping and ipv6_ping parameters are passed to a shell context without sanitization. An authenticated remote attacker can inject arbitrary operating system commands through these parameters. The exploit has been publicly disclosed and is tracked as VulDB entry VDB-252124. According to the disclosure, the vendor did not respond to early notification.
Critical Impact
Successful exploitation grants command execution on the device with the privileges of the web management process, allowing full compromise of the range extender and pivoting into the connected network.
Affected Products
- TRENDnet TEW-822DRE hardware device
- TRENDnet TEW-822DRE firmware version 1.03B02
- Deployments exposing the device web management interface to untrusted networks
Discovery Timeline
- 2024-01-26 - CVE-2024-0920 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-0920
Vulnerability Analysis
The TEW-822DRE web management interface exposes a diagnostic ping utility through /admin_ping.htm. When a user submits a POST request to trigger a ping test, the handler forwards the ipv4_ping or ipv6_ping parameter to an underlying system shell invocation. The handler does not validate that the input represents a well-formed IP address, nor does it escape shell metacharacters. This class of flaw is tracked as improper neutralization of special elements used in a command [CWE-77].
An attacker who reaches the authenticated web interface can supply a crafted parameter value containing shell separators such as ;, &&, or backticks. The injected commands execute in the context of the embedded web server, which typically runs with elevated privileges on consumer network devices. This enables credential theft, persistent implant deployment, and lateral movement into networks that trust the extender.
Root Cause
The root cause is the direct concatenation of user-supplied POST parameters into a shell command string without input validation or argument-safe execution. The handler treats the diagnostic input as trusted data and passes it to a shell interpreter.
Attack Vector
Exploitation requires network access to the device management interface and valid administrative credentials. Attackers commonly obtain these credentials through default password reuse, phishing, or LAN-side access. Once authenticated, the attacker submits a POST request to /admin_ping.htm containing a payload in ipv4_ping or ipv6_ping that appends shell commands after a valid or empty IP argument. The injected command executes on the device and returns control to the attacker.
No verified proof-of-concept code is published in a structured repository. Technical details are described in the VulDB entry #252124 and the independent Notion analysis document.
Detection Methods for CVE-2024-0920
Indicators of Compromise
- POST requests to /admin_ping.htm containing shell metacharacters such as ;, |, &, `, or $( in the ipv4_ping or ipv6_ping fields.
- Outbound connections from the TEW-822DRE to unexpected external hosts, particularly on non-standard ports.
- Unexpected child processes spawned by the device web server, such as wget, curl, tftp, nc, or sh invocations sourced from the ping handler.
Detection Strategies
- Inspect HTTP request bodies at network chokepoints for administrative POSTs targeting /admin_ping.htm with non-IP content in the ping parameters.
- Baseline management-interface traffic and alert on POST volumes or source addresses that deviate from administrator workstations.
- Correlate device configuration changes with authentication events to identify session abuse following credential compromise.
Monitoring Recommendations
- Restrict the device management VLAN and log all HTTP and HTTPS access to the extender from an out-of-band collector.
- Forward network telemetry and firewall logs to a centralized analytics platform so that anomalous outbound traffic from IoT devices surfaces alongside endpoint data.
- Track firmware versions across managed network gear to identify devices still running 1.03B02.
How to Mitigate CVE-2024-0920
Immediate Actions Required
- Remove the TEW-822DRE management interface from any untrusted or wireless-guest network segment.
- Rotate the administrative password on every deployed TEW-822DRE and disable any shared or default credentials.
- Block inbound WAN-side access to the web management interface at the perimeter firewall.
Patch Information
No vendor patch is currently referenced in the NVD or the disclosure record. The disclosure notes that TRENDnet did not respond to the researcher. Organizations should treat affected units as unpatched and plan for replacement or compensating controls. Monitor the TRENDnet support portal for future firmware advisories addressing the admin_ping.htm handler.
Workarounds
- Place the extender behind a network segment that only trusted administrator hosts can reach.
- Disable remote management features and enforce management access over a dedicated administrative VLAN.
- Replace the TEW-822DRE with a supported device if no firmware fix is issued for version 1.03B02.
# Example: restrict management access at an upstream firewall
# Allow only the admin workstation subnet to reach the extender web UI
iptables -A FORWARD -s 10.10.50.0/24 -d 192.0.2.25 -p tcp --dport 80 -j ACCEPT
iptables -A FORWARD -d 192.0.2.25 -p tcp --dport 80 -j DROP
iptables -A FORWARD -d 192.0.2.25 -p tcp --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
