CVE-2025-29137

Comprehensive Technical Analysis of CVE-2025-29137

1. Vulnerability Assessment and Severity Evaluation

CVE ID: CVE-2025-29137 CVSS Score: 9.8

The vulnerability in question is a buffer overflow in the form_fast_setting_wifi_set function of Tenda AC7 V1.0 V15.03.06.44, specifically triggered by the timeZone parameter. This vulnerability can lead to Remote Code Execution (RCE), making it highly critical. The CVSS score of 9.8 underscores the severity, indicating a high risk to the confidentiality, integrity, and availability of the affected system.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Network-Based Attack: An attacker can exploit this vulnerability over the network by sending a specially crafted request to the device.
• Local Exploitation: If an attacker has local access to the device, they can manipulate the timeZone parameter directly.

Exploitation Methods:

• Buffer Overflow: By sending a maliciously crafted timeZone parameter that exceeds the buffer size, an attacker can overwrite adjacent memory, potentially leading to arbitrary code execution.
• RCE: Once the buffer overflow is successfully exploited, the attacker can inject and execute malicious code on the device.

3. Affected Systems and Software Versions

Affected Systems:

• Tenda AC7 V1.0

Affected Software Versions:

• Firmware version V15.03.06.44

4. Recommended Mitigation Strategies

Immediate Actions:

• Patch Management: Apply the latest firmware update provided by Tenda as soon as it becomes available.
• Network Segmentation: Isolate the affected devices from critical networks to limit potential damage.
• Firewall Rules: Implement strict firewall rules to block unauthorized access to the device.

Long-Term Strategies:

• Regular Audits: Conduct regular security audits and vulnerability assessments.
• Intrusion Detection Systems (IDS): Deploy IDS to monitor and detect suspicious activities.
• User Education: Educate users on the importance of updating firmware and the risks associated with unpatched devices.

5. Impact on Cybersecurity Landscape

This vulnerability highlights the ongoing challenges in securing Internet of Things (IoT) devices. The potential for RCE in a widely used consumer device underscores the need for robust security measures in IoT firmware development and deployment. The high CVSS score indicates a significant risk, which could be exploited by threat actors to compromise home and small business networks.

6. Technical Details for Security Professionals

Vulnerability Details:

• Function: form_fast_setting_wifi_set
• Parameter: timeZone
• Issue: Buffer overflow due to insufficient input validation.

Exploitation Steps:

1. Identify Target: Locate the Tenda AC7 device on the network.
2. Craft Payload: Create a payload that exceeds the buffer size for the timeZone parameter.
3. Send Request: Send the crafted request to the device, triggering the buffer overflow.
4. Execute Code: Inject and execute arbitrary code on the device.

Detection and Response:

• Log Analysis: Monitor logs for unusual activity related to the form_fast_setting_wifi_set function.
• Behavioral Analysis: Use behavioral analysis tools to detect anomalous behavior indicative of a buffer overflow.
• Incident Response: Have an incident response plan in place to quickly address and mitigate any detected exploitation attempts.

References:

• Exploit Details

Conclusion

CVE-2025-29137 represents a critical vulnerability in Tenda AC7 devices that requires immediate attention. Organizations and individuals using these devices should prioritize firmware updates and implement robust security measures to mitigate the risk of exploitation. The cybersecurity community should continue to emphasize the importance of secure coding practices and regular updates to address such vulnerabilities effectively.