CVE-2022-33195 - Uncovering OS Command Injection Vulnerabilities in Abode iota All-In-One Security Kit

A recent discovery has uncovered four major OS command injection vulnerabilities in the XCMD testWifiAP functionality of the Abode Systems, Inc. iota All-In-One Security Kit versions 6.9X and 6.9Z. These vulnerabilities, identified as CVE-2022-33195, can lead to arbitrary command execution by an attacker if they manage to send a series of malicious commands to the device.

In this article, we will dive deep into the details of CVE-2022-33195, providing an in-depth analysis of the vulnerabilities including sample code snippets and references to the original research documents. We will also explore the ways in which these vulnerabilities can be exploited and mitigated.

Exploring the Vulnerabilities

The core issue behind these vulnerabilities lies in the unsafe use of the WL_DefaultKeyID parameter within the function at the offset x1c7d28 of the firmware version 6.9Z. Furthermore, the command execution occurring specifically at the offset x1c7fac worsens the situation.

We begin by inspecting the XCMD testWifiAP functionality to understand how the attacker can send malicious commands. Here's the relevant code snippet:

// Function at offset x1c7d28
void testWifiAP(const char *args) {
    ...
    // Unsafe use of WL_DefaultKeyID
    snprintf(cmd, sizeof(cmd), "wpa_passphrase \"%s\" \"%s\"", ssid, psk);
    ...
    // Command execution at offset x1c7fac
    FILE *fp = popen(cmd, "r");
    ...
}

In this code snippet, it is evident that the WL_DefaultKeyID parameter is being used unsafely within the snprintf function and then executed via the popen function. An attacker can exploit this vulnerability by providing carefully crafted input to the ssid and psk variables, leading to the execution of arbitrary commands on the system.

Exploiting the Vulnerabilities

An attacker exploiting these vulnerabilities would first need to craft a malicious XCMD command sequence to send to the device. For example, a possible payload might be:

// Crafted input as ssid
SSID=";reboot;"

// Crafted input as psk (password must meet wpa_passphrase requirements)
PSK="ThisIsAbc1234"

Here, the crafted ssid contains a semicolon delimiter which is used in shell commands to separate commands. By including this delimiter and a command (e.g., "reboot") afterward, the attacker essentially injects extra command code into the vulnerable snprintf function.

When this malicious input is processed by the testWifiAP function, it results in the following command being executed:

wpa_passphrase ";reboot;" "ThisIsAbc1234"

This command causes the device to reboot, effectively illustrating the potential for arbitrary command execution via these OS command injection vulnerabilities.

Mitigating the Risk

To mitigate the risks associated with CVE-2022-33195, it is essential to properly sanitize and validate the input received by the testWifiAP function. This can include ensuring that no shell metacharacters (such as ;, |, &, etc.) are present in user-provided input.

Additionally, it is highly recommended to update the iota All-In-One Security Kit's firmware to the latest patched version, which addresses these vulnerabilities.

If you're interested in exploring these vulnerabilities more, check out the following resources

- CVE-2022-33195 – NVD Details
- Abode Systems Security Advisory

Conclusion

CVE-2022-33195 demonstrates the importance of proper input validation and secure coding practices for embedded systems such as the iota All-In-One Security Kit by Abode Systems. By understanding these vulnerabilities and their potential impact, organizations can better prepare to protect their devices and networks from similar threats in the future.

Timeline

Published on: 10/25/2022 17:15:00 UTC
Last modified on: 10/26/2022 18:52:00 UTC