CVE-2023-40904

Comprehensive Technical Analysis of CVE-2023-40904

1. Vulnerability Assessment and Severity Evaluation

CVE ID: CVE-2023-40904 CVSS Score: 9.8

The vulnerability in question is a stack overflow in Tenda AC10 v4 US_AC10V4.0si_V16.03.10.13_cn, specifically within the parameters macFilterType and deviceList at the endpoint /goform/setMacFilterCfg. A stack overflow occurs when a program writes more data to a buffer located on the stack than what is actually allocated, leading to corruption of adjacent memory. This can result in arbitrary code execution, denial of service, or other unintended behaviors.

The CVSS score of 9.8 indicates a critical severity level. This high score is due to the potential for remote code execution, which can lead to complete system compromise. The vulnerability is classified as "Modified," suggesting that it has been acknowledged and possibly addressed by the vendor.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Remote Exploitation: An attacker can send specially crafted HTTP requests to the vulnerable endpoint /goform/setMacFilterCfg with malicious values for macFilterType and deviceList.
• Network-Based Attacks: Given that the Tenda AC10 is a network device, attackers can exploit this vulnerability over the network, potentially from the internet if the device is exposed.

Exploitation Methods:

• Buffer Overflow: By sending a large amount of data to the macFilterType and deviceList parameters, an attacker can overflow the stack buffer, leading to arbitrary code execution.
• Payload Delivery: An attacker can craft a payload that, when executed, provides them with remote access to the device or allows them to execute further malicious actions.

3. Affected Systems and Software Versions

Affected Systems:

• Tenda AC10 v4 devices running firmware version US_AC10V4.0si_V16.03.10.13_cn.

Software Versions:

• Specifically, the vulnerability affects the firmware version US_AC10V4.0si_V16.03.10.13_cn. Other versions may also be affected, but this has not been confirmed.

4. Recommended Mitigation Strategies

Immediate Actions:

• Firmware Update: Ensure that all Tenda AC10 v4 devices are updated to the latest firmware version provided by the vendor.
• Network Segmentation: Isolate network devices from public-facing networks to limit exposure.
• Firewall Rules: Implement strict firewall rules to restrict access to the management interface of the device.
• Intrusion Detection Systems (IDS): Deploy IDS to monitor for unusual traffic patterns that may indicate an exploitation attempt.

Long-Term Strategies:

• Regular Patch Management: Establish a routine for regularly updating firmware and software to mitigate known vulnerabilities.
• Security Audits: Conduct regular security audits and vulnerability assessments on network devices.
• User Education: Train users on the importance of network security and the risks associated with unpatched devices.

5. Impact on Cybersecurity Landscape

The discovery of this vulnerability highlights the ongoing challenge of securing IoT and network devices. The high CVSS score underscores the potential for significant damage if exploited, including unauthorized access, data breaches, and network disruptions. This vulnerability serves as a reminder of the importance of robust security practices, including timely patching and proactive monitoring.

6. Technical Details for Security Professionals

Exploit Details:

• Endpoint: /goform/setMacFilterCfg
• Parameters: macFilterType and deviceList
• Vulnerability Type: Stack Overflow
• Exploitation: Crafted HTTP requests with oversized data payloads can lead to stack corruption and arbitrary code execution.

References:

• Exploit and Third Party Advisory

Mitigation Steps:

1. Update Firmware: Ensure all Tenda AC10 v4 devices are running the latest firmware version.
2. Network Isolation: Segregate the device from public networks.
3. Firewall Configuration: Implement strict access controls to the management interface.
4. Monitoring: Use IDS/IPS to detect and respond to suspicious activity.

Conclusion: CVE-2023-40904 represents a critical vulnerability in Tenda AC10 v4 devices that requires immediate attention. By understanding the technical details and implementing the recommended mitigation strategies, organizations can significantly reduce the risk of exploitation and protect their network infrastructure.