EUVD-2025-35174

Comprehensive Technical Analysis of EUVD-2025-35174

1. Vulnerability Assessment and Severity Evaluation

The vulnerability described in EUVD-2025-35174 pertains to an improper host authentication mechanism in wolfSSH version 1.4.20 and earlier clients. This flaw allows for authentication bypass and the potential leaking of client credentials. The severity of this vulnerability is rated with a Base Score of 9.4 according to CVSS version 4.0, indicating a critical risk. The vector string CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/AU:Y/U:Red highlights several key aspects:

• Attack Vector (AV:N): The vulnerability can be exploited over the network.
• Attack Complexity (AC:L): The attack is of low complexity.
• Privileges Required (PR:N): No privileges are required to exploit the vulnerability.
• User Interaction (UI:P): Some form of user interaction is required.
• Confidentiality (VC:H), Integrity (VI:H), and Availability (VA:H): All are highly impacted.
• Scope Change (SC:H): The scope of the vulnerability is high.
• Impact on Confidentiality (SI:H), Integrity (SI:H), and Availability (SA:H): All are highly impacted.
• Authentication (AU:Y): Authentication is required.
• User (U:Red): The user is a reduced scope.

2. Potential Attack Vectors and Exploitation Methods

Given the nature of the vulnerability, potential attack vectors include:

• Network-Based Attacks: An attacker can exploit this vulnerability over the network, making it a significant threat for remote systems.
• Credential Leaking: The vulnerability allows for the leaking of client credentials, which can be used for further unauthorized access.
• Authentication Bypass: The improper authentication mechanism can be bypassed, allowing unauthorized access to systems and services.

Exploitation methods may involve:

• Man-in-the-Middle (MitM) Attacks: Intercepting and manipulating SSH communications to exploit the authentication bypass.
• Phishing and Social Engineering: Tricking users into interacting with malicious SSH servers to capture credentials.
• Automated Scripts: Using automated scripts to scan for vulnerable wolfSSH clients and exploit the vulnerability.

3. Affected Systems and Software Versions

The vulnerability affects wolfSSH version 1.4.20 and earlier clients. Organizations using these versions are at risk and should prioritize updating to a patched version.

4. Recommended Mitigation Strategies

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

• Update Software: Immediately update to the latest version of wolfSSH that addresses this vulnerability.
• Network Segmentation: Implement network segmentation to limit the exposure of vulnerable systems.
• Monitoring and Logging: Enhance monitoring and logging of SSH connections to detect and respond to suspicious activities.
• User Education: Educate users about the risks of phishing and social engineering attacks.
• Intrusion Detection Systems (IDS): Deploy IDS to detect and alert on potential exploitation attempts.
• Multi-Factor Authentication (MFA): Implement MFA to add an additional layer of security.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to the European cybersecurity landscape, particularly for organizations relying on wolfSSH for secure communications. The potential for credential leaking and authentication bypass can lead to widespread unauthorized access, data breaches, and loss of sensitive information. European organizations must prioritize patching and implementing robust security measures to mitigate this risk.

6. Technical Details for Security Professionals

For security professionals, the following technical details are crucial:

• Vulnerability Identification: The vulnerability is identified as CVE-2025-11625 and EUVD-2025-35174.
• References:
  • GitHub Pull Request: https://github.com/wolfSSL/wolfssh/pull/840
  • NVD Detail: https://nvd.nist.gov/vuln/detail/CVE-2025-11625
• Assigner: wolfSSL
• ENISA ID Product:
  • ID: 7c7a98bc-332b-3c73-bae9-94dde2667fdd
  • Product: wolfSSH
  • Version: 1.4.20;0
• ENISA ID Vendor:
  • ID: f92cf93f-e360-3662-8929-f3496d641dd8
  • Vendor: wolfSSH

Security professionals should review the provided references for detailed patch information and additional technical insights. Implementing a comprehensive security strategy that includes regular updates, monitoring, and user education is essential to protect against this and similar vulnerabilities.