EUVD-2025-11093

Comprehensive Technical Analysis of EUVD-2025-11093

1. Vulnerability Assessment and Severity Evaluation

The vulnerability EUVD-2025-11093 pertains to a stack overflow in the Totolink N600R v4.3.0cu.7647_B20210106 firmware, specifically within the setWanConfig function via the macCloneMac parameter. The CVSS (Common Vulnerability Scoring System) base score of 9.8 indicates a critical severity level. The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H breaks down as follows:

• Attack Vector (AV): Network (N) - The vulnerability can be exploited remotely over the network.
• Attack Complexity (AC): Low (L) - The attack requires minimal skill or resources.
• Privileges Required (PR): None (N) - No special privileges are needed to exploit the vulnerability.
• User Interaction (UI): None (N) - No user interaction is required for the attack to succeed.
• Scope (S): Unchanged (U) - The vulnerability affects the same security scope.
• Confidentiality (C): High (H) - The vulnerability can lead to a significant breach of confidentiality.
• Integrity (I): High (H) - The vulnerability can lead to a significant breach of integrity.
• Availability (A): High (H) - The vulnerability can lead to a significant breach of availability.

Given these metrics, the vulnerability poses a severe risk to affected systems, potentially leading to complete system compromise.

2. Potential Attack Vectors and Exploitation Methods

The stack overflow vulnerability in the setWanConfig function can be exploited by sending a specially crafted request to the device. Potential attack vectors include:

• Remote Exploitation: An attacker can send a malicious request over the network to trigger the stack overflow.
• Man-in-the-Middle (MitM) Attacks: An attacker could intercept and modify legitimate requests to include the malicious payload.
• Phishing: Users could be tricked into visiting a malicious website that sends the crafted request to their device.

Exploitation methods may involve:

• Buffer Overflow: Crafting a payload that exceeds the allocated buffer size for the macCloneMac parameter.
• Code Execution: Injecting malicious code that gets executed due to the overflow, leading to arbitrary code execution.
• Denial of Service (DoS): Causing the device to crash or become unresponsive.

3. Affected Systems and Software Versions

The vulnerability specifically affects the Totolink N600R router running firmware version v4.3.0cu.7647_B20210106. Other versions of the firmware and similar devices from Totolink may also be affected, but this requires further investigation.

4. Recommended Mitigation Strategies

To mitigate the risk associated with this vulnerability, the following strategies are recommended:

• Firmware Update: Immediately update the firmware to a patched version once available.
• Network Segmentation: Isolate the affected device from critical networks to limit potential damage.
• Firewall Rules: Implement strict firewall rules to block unauthorized access to the device.
• Intrusion Detection Systems (IDS): Deploy IDS to monitor for suspicious network activity targeting the setWanConfig function.
• User Education: Educate users about the risks of phishing and the importance of keeping firmware updated.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant threat to European cybersecurity, particularly for organizations and individuals using the affected Totolink N600R routers. The potential for remote exploitation and the high impact on confidentiality, integrity, and availability make it a critical concern. European cybersecurity agencies should issue advisories and work with vendors to ensure timely patches and updates.

6. Technical Details for Security Professionals

• Vulnerability Type: Stack Overflow
• Affected Function: setWanConfig
• Affected Parameter: macCloneMac
• Exploitation: The vulnerability can be triggered by sending a maliciously crafted request that exceeds the buffer size allocated for the macCloneMac parameter.
• Detection: Monitor network traffic for unusual patterns targeting the setWanConfig function. Implement logging and alerting mechanisms for suspicious activities.
• Patching: Ensure that the firmware update process is secure and verify the integrity of the update files.

Conclusion

The vulnerability EUVD-2025-11093 in the Totolink N600R router is critical and requires immediate attention. Organizations and individuals should prioritize updating their firmware and implementing robust security measures to mitigate the risk. European cybersecurity agencies should collaborate with vendors to ensure timely patches and updates, and issue advisories to raise awareness about the vulnerability.

References

• NVD Entry
• GitHub Repository

Aliases

• CVE-2025-22900
• GHSA-7jww-p4g2-4fpv