EUVD-2025-35865

Comprehensive Technical Analysis of EUVD-2025-35865

1. Vulnerability Assessment and Severity Evaluation

The vulnerability described in EUVD-2025-35865 pertains to a buffer overflow in the D-Link DIR600L Ax FW116WWb01 firmware. Specifically, the issue resides in the curTime parameter within the formSetWAN_Wizard52 function. The CVSS (Common Vulnerability Scoring System) base score of 9.8 indicates a critical severity level. The scoring 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 to exploit.
• 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 does not change the 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 factors, the vulnerability is highly critical and poses a significant risk to affected systems.

2. Potential Attack Vectors and Exploitation Methods

The buffer overflow vulnerability can be exploited through the following methods:

• Remote Code Execution (RCE): An attacker can send a specially crafted request to the device, causing a buffer overflow in the curTime parameter. This can lead to arbitrary code execution on the device.
• Denial of Service (DoS): By exploiting the buffer overflow, an attacker can crash the device, leading to a denial of service.
• Data Exfiltration: The attacker can potentially extract sensitive information from the device's memory, leading to a breach of confidentiality.

3. Affected Systems and Software Versions

The vulnerability specifically affects the D-Link DIR600L Ax FW116WWb01 firmware version. Other versions of the DIR600L Ax firmware may also be affected, but this has not been confirmed. It is crucial to verify the firmware version of all D-Link DIR600L Ax devices in use.

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 from D-Link.
• Network Segmentation: Isolate affected devices on a separate network segment to limit potential attack vectors.
• Firewall Rules: Implement strict firewall rules to restrict access to the device's management interface.
• Intrusion Detection Systems (IDS): Deploy IDS to monitor for suspicious network activity targeting the vulnerable parameter.
• Regular Audits: Conduct regular security audits and vulnerability assessments to identify and address similar issues proactively.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant threat to the European cybersecurity landscape, particularly for organizations and individuals using the affected D-Link devices. Given the widespread use of D-Link routers in both residential and commercial settings, the potential impact could be extensive. Organizations must prioritize patching and mitigation efforts to prevent potential breaches and ensure compliance with relevant cybersecurity regulations such as GDPR.

6. Technical Details for Security Professionals

For security professionals, the following technical details are pertinent:

• Vulnerable Function: formSetWAN_Wizard52
• Vulnerable Parameter: curTime
• Exploitation Method: Craft a malicious request targeting the curTime parameter to trigger the buffer overflow.
• Detection: Monitor network traffic for unusual patterns targeting the curTime parameter. Implement logging and alerting mechanisms for suspicious activities.
• Patching: Ensure that all D-Link DIR600L Ax devices are updated to the latest firmware version provided by D-Link.

References:

• GitHub Repository
• NVD Entry

By following these recommendations and staying vigilant, organizations can significantly reduce the risk posed by this critical vulnerability.