CVE-2026-78141 Overview
CVE-2026-78141 is a command injection vulnerability in the Tenda CH22 router running firmware version 1.0.0.1. The flaw resides in the formexeCommand function handling requests to /goform/exeCommand. Attackers manipulate the cmdinput parameter to inject arbitrary operating system commands. The issue is classified under CWE-74 for improper neutralization of special elements in downstream components. Public disclosure of the exploit details has occurred, increasing the risk of opportunistic scanning against exposed devices.
Critical Impact
Remote attackers with low privileges can inject shell commands through the cmdinput argument, potentially compromising the router's underlying operating system.
Affected Products
- Tenda CH22 router, firmware version 1.0.0.1
- Function formexeCommand within the device web management interface
- Endpoint /goform/exeCommand
Discovery Timeline
- 2026-08-23 - CVE-2026-78141 published to NVD
- 2026-08-27 - Last updated in NVD database
Technical Details for CVE-2026-78141
Vulnerability Analysis
The Tenda CH22 web management interface exposes a handler named formexeCommand bound to the /goform/exeCommand route. This handler reads the cmdinput argument from an HTTP request and passes it to an underlying shell execution routine without sufficient neutralization. An attacker who reaches the interface can supply shell metacharacters within cmdinput to append or chain additional operating system commands. Successful injection executes commands with the privileges of the router web service, which on embedded Tenda devices typically runs as root. The public disclosure of proof-of-concept material lowers the barrier to weaponization against internet-exposed devices.
Root Cause
The root cause is improper input neutralization ([CWE-74]) in the formexeCommand handler. The function forwards user-controlled data from cmdinput into a system shell context without validating, escaping, or restricting the character set. As a result, characters such as ;, |, &, and backticks retain their shell semantics.
Attack Vector
Exploitation occurs over the network against the router administration interface. The attacker submits a crafted HTTP request to /goform/exeCommand with a malicious cmdinput value. The CVSS 4.0 vector indicates the attacker requires low-level authentication on the device to reach the vulnerable endpoint. No user interaction is required.
// No verified proof-of-concept code is published in the referenced advisories.
// See the Notion analysis and VulDB entries linked in the references for details.
Detection Methods for CVE-2026-78141
Indicators of Compromise
- HTTP POST or GET requests targeting the path /goform/exeCommand on Tenda CH22 devices.
- Request bodies or query strings containing shell metacharacters (;, |, &, `, $()) within the cmdinput parameter.
- Unexpected outbound connections from the router to attacker-controlled infrastructure following administrative requests.
Detection Strategies
- Inspect HTTP traffic to router management interfaces for unusual cmdinput values on the /goform/exeCommand endpoint.
- Alert on administrative authentication events followed by requests containing command-chaining syntax.
- Correlate router-originated DNS, ICMP, or TCP callbacks with recent web management activity from non-administrative source addresses.
Monitoring Recommendations
- Log and forward router web server access logs to a central analytics platform for retention and query.
- Monitor for firmware version 1.0.0.1 on Tenda CH22 devices during periodic asset discovery scans.
- Track EPSS movement for CVE-2026-78141 to prioritize response as exploitation likelihood evolves.
How to Mitigate CVE-2026-78141
Immediate Actions Required
- Restrict access to the router administration interface to trusted management VLANs or hosts only.
- Disable remote WAN-side management on affected Tenda CH22 devices until a fix is available.
- Rotate administrator credentials and enforce strong passphrases to raise the barrier for the low-privilege precondition.
Patch Information
No vendor patch is referenced in the current advisory data for CVE-2026-78141. Consult the Tenda Official Website and the VulDB CVE-2026-78141 Entry for future firmware updates. Additional technical analysis is available in the Notion Command Execution Analysis.
Workarounds
- Place the router behind a network segment that blocks untrusted access to TCP ports serving the web management interface.
- Use access control lists on upstream firewalls to permit management traffic only from a defined administrator subnet.
- Consider replacing end-of-life or unpatched Tenda CH22 devices in environments where mitigation cannot be enforced.
# Example iptables rule limiting router web management access to a trusted admin host
iptables -A INPUT -p tcp --dport 80 -s 192.0.2.10 -j ACCEPT
iptables -A INPUT -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.
