CVE-2023-41553

Comprehensive Technical Analysis of CVE-2023-41553

1. Vulnerability Assessment and Severity Evaluation

CVE ID: CVE-2023-41553 CVSS Score: 9.8

The vulnerability in question is a stack overflow in Tenda AC9 V3.0 V15.03.06.42_multi and Tenda AC5 US_AC5V1.0RTL_V15.03.06.28. This vulnerability is triggered via a parameter list at the URL /goform/SetStaticRouteCfg. The high CVSS score of 9.8 indicates that this vulnerability is critical and poses a significant risk to affected systems.

Severity Evaluation:

• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: High

The high severity is due to the potential for remote code execution (RCE), which can lead to complete system compromise, including unauthorized access to sensitive information, modification of system settings, and denial of service.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Remote Exploitation: An attacker can exploit this vulnerability remotely by sending a specially crafted HTTP request to the vulnerable endpoint.
• Network-Based Attacks: Given that the vulnerability is in a network device, attackers can leverage network-based attacks to exploit the stack overflow.

Exploitation Methods:

• Buffer Overflow: The attacker can send a large amount of data in the parameter list to overflow the stack buffer.
• Code Injection: By carefully crafting the input, an attacker can inject malicious code that gets executed on the device.
• Denial of Service (DoS): Even if code execution is not achieved, the stack overflow can cause the device to crash, leading to a DoS condition.

3. Affected Systems and Software Versions

Affected Systems:

• Tenda AC9 V3.0 with firmware version V15.03.06.42_multi
• Tenda AC5 with firmware version US_AC5V1.0RTL_V15.03.06.28

Software Versions:

• The specific firmware versions mentioned above are known to be vulnerable. Other versions may also be affected but have not been explicitly identified.

4. Recommended Mitigation Strategies

Immediate Actions:

• Firmware Update: Apply the latest firmware updates provided by Tenda. Ensure that the firmware version is higher than the affected versions.
• Network Segmentation: Isolate the affected devices from critical networks to limit the potential impact of an exploit.
• Firewall Rules: Implement strict firewall rules to restrict access to the vulnerable endpoint (/goform/SetStaticRouteCfg).

Long-Term Strategies:

• Regular Patching: Establish a regular patching and update schedule for all network devices.
• Intrusion Detection Systems (IDS): Deploy IDS to monitor for suspicious activity and potential exploitation attempts.
• Security Audits: Conduct regular security audits and vulnerability assessments to identify and mitigate similar issues.

5. Impact on Cybersecurity Landscape

The discovery of this vulnerability highlights the ongoing challenge of securing network devices, particularly those used in home and small office environments. The potential for remote code execution underscores the need for robust security measures and regular updates. This vulnerability also serves as a reminder of the importance of secure coding practices to prevent stack overflows and other common vulnerabilities.

6. Technical Details for Security Professionals

Vulnerability Details:

• Endpoint: /goform/SetStaticRouteCfg
• Parameter List: The vulnerability is triggered by manipulating the parameter list in the HTTP request.
• Stack Overflow: The stack overflow occurs due to insufficient bounds checking on the input data.

Exploitation Steps:

1. Identify Target: Identify the target device running the vulnerable firmware version.
2. Craft Payload: Create a payload that exceeds the buffer size for the parameter list.
3. Send Request: Send the crafted HTTP request to the vulnerable endpoint.
4. Execute Code: If successful, the payload will execute arbitrary code on the device.

Detection and Monitoring:

• Log Analysis: Monitor logs for unusual activity related to the /goform/SetStaticRouteCfg endpoint.
• Anomaly Detection: Use anomaly detection tools to identify abnormal traffic patterns that may indicate an exploitation attempt.
• Network Traffic Analysis: Analyze network traffic for large or malformed HTTP requests targeting the vulnerable endpoint.

Conclusion: CVE-2023-41553 represents a critical vulnerability in Tenda network devices that requires immediate attention. Organizations and individuals using the affected devices should prioritize firmware updates and implement robust security measures to mitigate the risk of exploitation. Continuous monitoring and regular security assessments are essential to maintain a strong security posture.