EUVD-2025-8766

Comprehensive Technical Analysis of EUVD-2025-8766

1. Vulnerability Assessment and Severity Evaluation

The vulnerability identified in EUVD-2025-8766 pertains to the Adtran 411 ONT L80.00.0011.M2 device, which contains weak default passwords. 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:

• AV:N (Attack Vector: Network): The vulnerability can be exploited remotely over the network.
• AC:L (Attack Complexity: Low): The attack requires low skill or resources to exploit.
• PR:N (Privileges Required: None): No privileges are required to exploit the vulnerability.
• UI:N (User Interaction: None): No user interaction is required to exploit the vulnerability.
• S:U (Scope: Unchanged): The vulnerability does not change the security scope.
• C:H (Confidentiality: High): The vulnerability has a high impact on confidentiality.
• I:H (Integrity: High): The vulnerability has a high impact on integrity.
• A:H (Availability: High): The vulnerability has a high impact on availability.

Given these metrics, the vulnerability is highly exploitable and can lead to severe consequences if not addressed promptly.

2. Potential Attack Vectors and Exploitation Methods

The primary attack vector for this vulnerability is the use of default credentials to gain unauthorized access to the Adtran 411 ONT device. Potential exploitation methods include:

• Brute Force Attacks: Attackers can use automated tools to attempt common default passwords.
• Credential Stuffing: Attackers may use known default credentials to access the device.
• Network Scanning: Attackers can scan networks for devices with default credentials and exploit them.

Once access is gained, attackers can:

• Modify Configuration Settings: Change settings to disrupt network operations.
• Extract Sensitive Information: Access and exfiltrate sensitive data.
• Install Malware: Deploy malicious software to further compromise the network.

3. Affected Systems and Software Versions

The vulnerability specifically affects the Adtran 411 ONT device running firmware version L80.00.0011.M2. It is crucial to identify all instances of this device within the network and ensure they are updated to a secure firmware version.

4. Recommended Mitigation Strategies

To mitigate this vulnerability, the following steps should be taken:

• Change Default Passwords: Immediately change the default passwords to strong, unique passwords.
• Firmware Update: Apply the latest firmware updates provided by Adtran to address the vulnerability.
• Network Segmentation: Implement network segmentation to limit the exposure of vulnerable devices.
• Monitoring and Logging: Enable logging and monitoring to detect any unauthorized access attempts.
• Access Control: Implement strict access control policies to limit who can access and configure the devices.

5. Impact on European Cybersecurity Landscape

The presence of weak default passwords in widely deployed devices like the Adtran 411 ONT can have significant implications for European cybersecurity. Organizations and critical infrastructure providers relying on these devices are at risk of unauthorized access, data breaches, and service disruptions. This vulnerability underscores the need for robust cybersecurity practices and regular audits of network devices.

6. Technical Details for Security Professionals

For security professionals, the following technical details are pertinent:

• Vulnerability Identification: The vulnerability is identified by EUVD-2025-8766 and CVE-2025-22938.
• References: Additional information can be found at the provided references:
  • Google Drive Document
  • NVD Entry
• Assigner: The vulnerability was assigned by Mitre.
• EPSS: The Exploit Prediction Scoring System (EPSS) score is not available, indicating that the likelihood of exploitation in the wild is not yet quantified.
• ENISA ID: The ENISA ID for the product and vendor is not available, suggesting that further details may be forthcoming.

In conclusion, the vulnerability in the Adtran 411 ONT L80.00.0011.M2 device poses a critical risk due to weak default passwords. Immediate action is required to change default credentials, update firmware, and implement robust security measures to protect against potential exploitation.