CVE-2022-37799 in AC1206
Summary
by MITRE • 08/25/2022
Tenda AC1206 V15.03.06.23 was discovered to contain a stack overflow via the time parameter at the function setSmartPowerManagement.
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Analysis
by VulDB Data Team • 10/01/2022
The vulnerability identified as CVE-2022-37799 affects the Tenda AC1206 router firmware version V15.03.06.23 and represents a critical stack overflow condition that can be exploited through the time parameter within the setSmartPowerManagement function. This issue resides in the router's web interface handling mechanism, where improper input validation allows malicious actors to craft specifically formatted time values that exceed the allocated stack buffer space. The vulnerability stems from inadequate bounds checking and memory management practices within the firmware's web server component, creating an exploitable condition that could lead to arbitrary code execution or system compromise. The affected device operates with a stack-based buffer overflow scenario where the time parameter is directly processed without sufficient validation to prevent buffer overflows.
The technical flaw manifests when the setSmartPowerManagement function receives user-supplied time data through the web interface, typically used for configuring smart power management schedules. The function fails to properly validate the length of the time parameter input, allowing an attacker to provide excessively long input strings that overwrite adjacent stack memory locations. This type of vulnerability maps directly to CWE-121 Stack-based Buffer Overflow, which is classified as a critical weakness in software security. The buffer overflow occurs because the firmware does not implement proper input length checks or use safe string handling functions that would prevent memory corruption during parameter processing. The attack vector is particularly concerning as it requires no authentication to exploit, making it accessible through unauthenticated network requests to the router's web management interface.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable complete system compromise and unauthorized access to the affected router. An attacker who successfully exploits this vulnerability could execute arbitrary code with the privileges of the web server process, potentially gaining root access to the device and establishing persistent control over the network infrastructure. The compromised router could then be used as a pivot point for attacking other devices on the local network or as a command and control server for botnet operations. Additionally, the vulnerability could enable attackers to modify router configurations, steal network credentials, or redirect traffic through malicious proxies, creating significant security implications for any organization or individual using the affected device. This vulnerability directly aligns with ATT&CK technique T1059.007 Command and Scripting Interpreter: PowerShell, as the exploitation may involve command execution capabilities that can be leveraged for further compromise.
Mitigation strategies for CVE-2022-37799 should prioritize immediate firmware updates from Tenda, as the vendor has likely released patches addressing this specific buffer overflow condition. Network administrators should implement network segmentation and access controls to limit exposure to this vulnerability, particularly by restricting access to the router's web management interface from untrusted networks. The implementation of intrusion detection systems capable of identifying malformed HTTP requests targeting the specific function could provide additional defense-in-depth measures. Organizations should also consider disabling unnecessary web management interfaces and implementing secure remote access methods such as VPN connections for authorized administrators. Regular firmware updates and security assessments of network infrastructure are essential practices to prevent exploitation of similar vulnerabilities, as this issue demonstrates the ongoing need for proper input validation and secure coding practices in embedded systems. The vulnerability underscores the importance of applying security patches promptly and maintaining awareness of known vulnerabilities in network equipment to prevent exploitation by threat actors.