CVE-2023-41557

Comprehensive Technical Analysis of CVE-2023-41557

1. Vulnerability Assessment and Severity Evaluation

CVE ID: CVE-2023-41557 CVSS Score: 9.8

The vulnerability in question is a stack overflow in Tenda AC7 V1.0 V15.03.06.44 and Tenda AC5 V1.0RTL_V15.03.06.28 devices. The stack overflow occurs via the parameters entrys and mitInterface at the URL /goform/addressNat.

Severity Evaluation:

• CVSS Score: 9.8 (Critical)
• Impact: This vulnerability can lead to remote code execution (RCE), allowing an attacker to execute arbitrary code on the affected device.
• Exploitability: The vulnerability can be exploited remotely, making it highly dangerous.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Remote Exploitation: An attacker can send specially crafted HTTP requests to the vulnerable endpoint /goform/addressNat with malicious parameters entrys and mitInterface.
• Network-Based Attacks: Given that the devices are often used in home and small office environments, they are typically exposed to the internet, making them prime targets for remote attacks.

Exploitation Methods:

• Buffer Overflow: By sending a large amount of data in the entrys and mitInterface parameters, an attacker can overflow the stack buffer, leading to code execution.
• Payload Delivery: The attacker can inject malicious code into the overflowed buffer, which can then be executed by the device.

3. Affected Systems and Software Versions

Affected Devices:

• Tenda AC7 V1.0 with firmware version V15.03.06.44
• Tenda AC5 V1.0 with firmware version RTL_V15.03.06.28

Software Versions:

• The vulnerability specifically affects the firmware versions mentioned above. Other versions may also be affected but have not been explicitly tested or reported.

4. Recommended Mitigation Strategies

Immediate Actions:

• Firmware Update: Users should immediately update their devices to the latest firmware version provided by Tenda.
• Network Segmentation: Isolate the affected devices from the internet or place them behind a firewall to limit exposure.
• Monitoring: Implement network monitoring to detect and respond to any suspicious activity targeting the vulnerable endpoint.

Long-Term Strategies:

• Regular Patching: Establish a regular patching and update schedule for all network devices.
• Security Audits: Conduct regular security audits and vulnerability assessments to identify and mitigate potential vulnerabilities.
• Intrusion Detection Systems (IDS): Deploy IDS to detect and alert on any attempts to exploit known vulnerabilities.

5. Impact on Cybersecurity Landscape

Broader Implications:

• IoT Security: This vulnerability highlights the ongoing challenges in securing Internet of Things (IoT) devices, which are often deployed in large numbers and are difficult to update.
• Supply Chain Risks: The vulnerability in widely used consumer devices underscores the risks associated with supply chain security and the need for vendors to prioritize security in their products.
• Remote Workforce: With the increase in remote work, the security of home networks and devices has become critical, as they can serve as entry points for attacks on corporate networks.

6. Technical Details for Security Professionals

Exploit Details:

• Endpoint: /goform/addressNat
• Parameters: entrys and mitInterface
• Vulnerability Type: Stack Overflow
• Exploit Code: The exploit code is available in the referenced GitHub repository, which provides detailed steps on how the vulnerability can be exploited.

Mitigation Steps:

• Code Review: Conduct a thorough code review of the firmware to identify and fix similar vulnerabilities.
• Input Validation: Implement robust input validation to prevent buffer overflows.
• Memory Management: Ensure proper memory management practices to avoid stack overflows and other memory-related vulnerabilities.

References:

• GitHub Repository

By addressing this vulnerability promptly and implementing robust security measures, organizations can significantly reduce the risk of exploitation and protect their networks from potential attacks.