CVE-2024-4064 in AC8
Summary
by MITRE • 04/23/2024
A vulnerability was found in Tenda AC8 16.03.34.09. It has been declared as critical. This vulnerability affects the function R7WebsSecurityHandler of the file /goform/execCommand. The manipulation of the argument password leads to stack-based buffer overflow. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. VDB-261790 is the identifier assigned to this vulnerability. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.
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Analysis
by VulDB Data Team • 01/22/2025
The vulnerability identified as CVE-2024-4064 represents a critical stack-based buffer overflow flaw in the Tenda AC8 router firmware version 16.03.34.09. This vulnerability resides within the R7WebsSecurityHandler function located in the /goform/execCommand file, making it a prime target for remote exploitation. The flaw specifically manifests when the password argument is manipulated, allowing attackers to overflow the stack buffer and potentially execute arbitrary code on the affected device. The vulnerability's classification as critical stems from its remote exploitability and the fact that a public exploit has already been disclosed, as indicated by VDB-261790 identifier. This represents a significant security risk for users who have not yet patched their devices, as the attack vector does not require physical access or complex social engineering.
The technical nature of this vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows an attacker to overwrite adjacent memory locations. The exploitation occurs through the manipulation of the password parameter in the execCommand function, which likely lacks proper input validation and bounds checking. When an attacker sends a specially crafted password string that exceeds the allocated buffer size, the excess data overflows into adjacent stack memory, potentially corrupting the return address or other critical program state. This type of vulnerability typically allows for privilege escalation and arbitrary code execution, making it particularly dangerous for network devices that serve as gateways to home or office networks.
The operational impact of CVE-2024-4064 extends beyond simple remote code execution, as compromised routers can serve as persistent footholds for attackers to conduct further network reconnaissance and lateral movement. Once an attacker gains control of the router, they can modify network traffic, redirect DNS queries, or establish backdoors that persist even after device reboots. The vulnerability's presence in a consumer-grade router like the Tenda AC8 means that it affects numerous end-users who may not be aware of the security implications or have the technical knowledge to implement proper mitigations. The lack of vendor response to early disclosure attempts compounds the risk, as users have no official patch or mitigation guidance from the manufacturer, leaving them vulnerable to active exploitation.
Organizations and individuals should immediately implement mitigations including network segmentation to isolate affected devices, disabling unnecessary remote management features, and changing default credentials to strong, unique passwords. Network monitoring should be enhanced to detect unusual traffic patterns that might indicate exploitation attempts, particularly focusing on traffic to the /goform/execCommand endpoint. The ATT&CK framework's T1071.001 technique for application layer protocol: web protocols should be considered when analyzing network traffic for signs of exploitation. Additionally, network administrators should consider implementing network access control lists to restrict access to the router's management interface from untrusted networks and ensure that all firmware updates are applied as soon as patches become available from the vendor, even if the vendor has not yet acknowledged the vulnerability.