EUVD-2025-16940

Comprehensive Technical Analysis of EUVD-2025-16940

1. Vulnerability Assessment and Severity Evaluation

Vulnerability Description: The vulnerability EUVD-2025-16940 affects the D-Link DIR-816 router, specifically version 1.10CNB05. It involves a stack-based buffer overflow in the qosClassifier function within the file /goform/qosClassifier. The vulnerability is triggered by manipulating the dip_address or sip_address arguments.

Severity Evaluation:

• Base Score: 9.3 (CVSS 4.0)
• Base Score Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

The high base score indicates a critical vulnerability. Key factors contributing to this severity include:

• Attack Vector (AV:N): The vulnerability can be exploited remotely over the network.
• Attack Complexity (AC:L): The attack is of low complexity, requiring minimal skill to exploit.
• Privileges Required (PR:N): No special privileges are needed to exploit the vulnerability.
• User Interaction (UI:N): No user interaction is required for the attack to succeed.
• Confidentiality, Integrity, and Availability Impact (VC:H, VI:H, VA:H): The vulnerability has a high impact on confidentiality, integrity, and availability.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Remote Exploitation: An attacker can exploit this vulnerability over the network without needing physical access to the device.
• Buffer Overflow: By manipulating the dip_address or sip_address arguments, an attacker can cause a stack-based buffer overflow, leading to arbitrary code execution.

Exploitation Methods:

• Crafted Packets: An attacker can send specially crafted network packets to the router, targeting the qosClassifier function.
• Public Exploit: The exploit has been disclosed to the public, making it readily available for malicious actors to use.

3. Affected Systems and Software Versions

Affected Systems:

• D-Link DIR-816 Router
• Firmware Version: 1.10CNB05

Note: This vulnerability only affects products that are no longer supported by the maintainer, making it particularly concerning for users who have not upgraded their devices.

4. Recommended Mitigation Strategies

Immediate Mitigation:

• Network Segmentation: Isolate the affected routers from critical network segments to limit potential damage.
• Firewall Rules: Implement strict firewall rules to block unauthorized access to the router's management interface.
• Monitoring: Increase monitoring of network traffic to detect any suspicious activities targeting the router.

Long-Term Mitigation:

• Firmware Upgrade: Although the affected version is no longer supported, users should consider upgrading to a newer, supported model if possible.
• Patch Management: Regularly check for and apply any available patches or updates from D-Link.
• Security Best Practices: Follow best practices for router security, including changing default credentials and disabling unnecessary services.

5. Impact on European Cybersecurity Landscape

Impact Analysis:

• Widespread Use: D-Link routers are widely used in both residential and small business environments across Europe.
• Critical Infrastructure: Although primarily used in home and small office settings, the vulnerability could impact critical infrastructure if these routers are used in such environments.
• Public Disclosure: The public disclosure of the exploit increases the risk of widespread attacks, potentially leading to significant disruptions.

Regulatory and Compliance:

• GDPR Compliance: Organizations must ensure that their network security measures comply with GDPR regulations to protect personal data.
• NIS Directive: Critical infrastructure operators must adhere to the Network and Information Systems (NIS) Directive, which mandates robust cybersecurity measures.

6. Technical Details for Security Professionals

Technical Analysis:

• Vulnerable Function: qosClassifier
• Affected File: /goform/qosClassifier
• Vulnerable Arguments: dip_address, sip_address
• Exploit Type: Stack-based buffer overflow
• Remote Exploitation: Yes

Detection and Response:

• Intrusion Detection Systems (IDS): Configure IDS to detect anomalous traffic patterns targeting the qosClassifier function.
• Incident Response: Develop an incident response plan specifically for this vulnerability, including steps for containment, eradication, and recovery.
• Log Analysis: Regularly analyze router logs for any signs of exploitation attempts.

References:

• VulDB Entry
• CTIID Entry
• Submission Details
• GitHub Repository
• D-Link Official Website
• NVD Entry

Aliases:

• CVE-2025-5623

Assigner:

• VulDB

EPSS:

• N/A

ENISA ID Product:

• [{"id":"dd74ec8c-89bf-3467-8959-cc36c4090d94","product":{"name":"DIR-816"},"product_version":"1.10CNB05"}]

ENISA ID Vendor:

• [{"id":"57e844c1-2d32-3258-8a8f-3eff7c3b2d76","vendor":{"name":"D-Link"}}]

This comprehensive analysis provides a detailed overview of the vulnerability, its potential impact, and recommended mitigation strategies for cybersecurity professionals.