CVE-2024-0541 in Tenda
Summary
by MITRE • 01/15/2024
A vulnerability was found in Tenda W9 1.0.0.7(4456). It has been declared as critical. Affected by this vulnerability is the function formAddSysLogRule of the component httpd. The manipulation of the argument sysRulenEn leads to stack-based buffer overflow. The attack can be launched remotely. The exploit has been disclosed to the public and may be used. The associated identifier of this vulnerability is VDB-250711. 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 • 02/03/2024
The vulnerability identified as CVE-2024-0541 represents a critical stack-based buffer overflow flaw in the Tenda W9 router firmware version 1.0.0.7(4456) affecting the httpd web server component. This issue resides within the formAddSysLogRule function where the sysRulenEn argument is processed without adequate bounds checking, creating a exploitable condition that allows attackers to manipulate memory layout through carefully crafted input data. The vulnerability's classification as critical stems from its remote exploitability and the disclosed public exploit availability, making it a significant threat to network security. The attack vector requires no authentication and can be executed over the network, targeting the router's web interface where the vulnerable function handles system log rule configuration parameters.
The technical nature of this vulnerability aligns with CWE-121, stack-based buffer overflow, where insufficient validation of input parameters allows an attacker to write beyond allocated memory boundaries in the stack. When the sysRulenEn argument is processed, the lack of proper input sanitization enables an attacker to overflow the buffer and potentially overwrite adjacent stack memory, including return addresses and function pointers. This type of vulnerability provides attackers with opportunities to execute arbitrary code on the affected device, potentially leading to complete system compromise. The attack can be launched remotely through the web interface, making it particularly dangerous as it requires no physical access or local network presence to exploit.
The operational impact of this vulnerability extends beyond simple remote code execution to encompass complete network device takeover, allowing adversaries to gain persistent access to the affected router. Once exploited, attackers can manipulate network traffic routing, modify firewall rules, access sensitive configuration data, and potentially use the compromised device as a pivot point for attacking other systems within the local network. The vulnerability's exploitation may also result in denial of service conditions, where the device becomes unresponsive or reboots continuously due to memory corruption. Given that this is a web-based interface vulnerability, it affects all users who have access to the router's management interface, making the attack surface particularly wide.
Security mitigations for this vulnerability should include immediate firmware updates from Tenda if available, though the vendor's lack of response to early disclosure raises concerns about patch availability. Network segmentation and access control measures can help limit the potential impact by restricting access to the router's management interface to trusted networks only. Implementing network monitoring solutions that detect unusual traffic patterns or attempted exploitation attempts can provide early warning of attacks. Organizations should also consider disabling unnecessary web management interfaces and using secure protocols such as HTTPS with strong authentication when access is required. The vulnerability demonstrates the importance of proper input validation and memory safety practices in embedded systems, aligning with ATT&CK technique T1210 for exploitation of remote services and T1059 for command and script injection. Regular vulnerability assessments of network infrastructure components and maintaining updated threat intelligence on disclosed vulnerabilities are essential defensive measures against such threats.