CVE-2022-36233 in AC9
Summary
by MITRE • 08/20/2022
Tenda AC9 V15.03.2.13 is vulnerable to Buffer Overflow via httpd, form_fast_setting_wifi_set. httpd.
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Analysis
by VulDB Data Team • 07/07/2026
The vulnerability identified as CVE-2022-36233 affects the Tenda AC9 router model running firmware version V15.03.2.13 and represents a critical buffer overflow condition within the web server component. This issue manifests specifically through the httpd service when processing requests to the form_fast_setting_wifi_set endpoint, creating a potential pathway for remote code execution and system compromise. The vulnerability stems from inadequate input validation and memory management practices within the router's web interface handling mechanism.
The technical flaw occurs when the httpd service processes user-supplied data through the form_fast_setting_wifi_set function without proper bounds checking or sanitization. This allows an attacker to craft malicious input that exceeds the allocated buffer space, causing memory corruption that can be exploited to overwrite adjacent memory locations. The buffer overflow vulnerability falls under CWE-121 which specifically addresses stack-based buffer overflow conditions, while also aligning with CWE-787 which covers out-of-bounds write vulnerabilities. The exploitation of this condition can potentially lead to arbitrary code execution with the privileges of the web server process, typically running with elevated system privileges.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as it provides attackers with a potential foothold for more extensive network compromise. An attacker could leverage this vulnerability to execute malicious code on the affected router, potentially gaining access to the internal network, redirecting traffic, or using the device as a pivot point for further attacks. The attack surface is particularly concerning given that routers often serve as network gateways and are frequently exposed to external networks. This vulnerability aligns with ATT&CK technique T1059 which covers command and scripting interpreter, and T1021 which addresses remote services, as the compromised device could be used to establish persistent access or launch additional attacks.
Mitigation strategies for CVE-2022-36233 should prioritize immediate firmware updates from Tenda to address the buffer overflow condition. Network administrators should also implement network segmentation to limit the potential impact of exploitation and monitor for unusual traffic patterns that might indicate compromise. Additional protective measures include disabling unnecessary services, implementing strong access controls for the web interface, and regularly auditing router configurations. The vulnerability demonstrates the importance of secure coding practices and input validation in embedded systems, as proper bounds checking and memory management could prevent the buffer overflow condition from occurring. Organizations should also consider implementing intrusion detection systems to monitor for exploitation attempts and maintain current threat intelligence regarding similar vulnerabilities in networking equipment.