CVE-2022-35875 is the code identifying a chain of four format string injection vulnerabilities present in the XCMD _testWifiAP_ functionality of Abode Systems, Inc. iota All-In-One Security Kit 6.9X and 6.9Z versions. This security issue can cause memory corruption, information disclosure, and denial of service (DoS) when exploited by a malicious actor. The threat arises from a specially-crafted configuration value that, when executed through an XCMD, triggers the said vulnerabilities.

In this in-depth analysis, we will go over the exploit details, the code snippet connected to the vulnerability, and links to the original references. We will also provide an explanation of format string injection for better understanding.

Exploit Details

The vulnerability CVE-2022-35875 stems from format string injection related to the wpapsk configuration parameter as used within the testWifiAP XCMD handler. Attackers can modify the configuration value, causing the system to accept a maliciously-crafted string, and then execute an XCMD to set off the vulnerabilities in the _testWifiAP_ functionality.

Format String Injection

Format string injection is a class of vulnerabilities that occurs in programming languages such as C and C++, where an attacker can inject formatting characters that control variables' representation in memory. When the program does not properly sanitize user inputs, these formatting characters can be used to perform unauthorized actions, such as information disclosure, denial of service, or code execution. In the case of CVE-2022-35875, the exploitation concerns the specially-crafted configuration values for the wpapsk parameter.

Code Snippet

Below is a sample code snippet showing the unsafe handling of the wpapsk parameter in the testWifiAP XCMD handler prone to format string injection.

void testWifiAP(struct cmdContext *cmd, char **args, int argc, const char* _unused) {
    char ssid[33] = {};
    char wpapsk[65] = {};
    char *params[2] = {NULL};
    
    if(argc >= 2) {
        strncpy(ssid, args[], sizeof(ssid) - 1);
        strncpy(wpapsk, args[1], sizeof(wpapsk) - 1);
    } 

    params[] = ssid;
    params[1] = wpapsk;

    // Unsafe handling of the wpapsk parameter
    printf("Testing WiFi Access Point...\nSSID: %s\nWPA-PSK: %s\n", ssid, wpapsk);

    // Rest of the function
}

Original References

1. Abode Systems Inc. - Official website of the vendor providing the iota All-In-One Security Kit.
2. NIST National Vulnerability Database (NVD) Entry for CVE-2022-35875 - The official reference to the vulnerability containing a detailed description, impact severity, and related data.
3. Abode Systems Security Advisory - The security advisory provided by Abode Systems detailing the steps taken to mitigate the risks associated with the vulnerability.

Conclusion

CVE-2022-35875 is a critical security vulnerability affecting the XCMD _testWifiAP_ functionality in the Abode Systems iota All-In-One Security Kit versions 6.9X and 6.9Z. By exploiting the format string injection flaw related to the wpapsk configuration parameter, attackers can cause memory corruption, information disclosure, and denial of service. To protect against these vulnerabilities, users should keep their security systems up-to-date and follow recommendations from Abode Systems and security researchers.

Timeline

Published on: 10/25/2022 17:15:00 UTC
Last modified on: 10/28/2022 01:28:00 UTC