EUVD-2024-0460

Comprehensive Technical Analysis of EUVD-2024-0460

1. Vulnerability Assessment and Severity Evaluation

The vulnerability in Nginx-UI, identified as EUVD-2024-0460 (CVE-2024-23827, GHSA-xvq9-4vpv-227m), is a critical issue that allows arbitrary file writes through the Import Certificate feature. This vulnerability can be exploited to overwrite system files, including configuration files like app.ini, potentially leading to remote code execution (RCE).

Severity Evaluation:

• CVSS Base Score: 9.8
• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

The high CVSS score indicates a severe vulnerability due to its network accessibility, low complexity, and the lack of required privileges or user interaction. The impact on confidentiality, integrity, and availability is high.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Remote Exploitation: An attacker can exploit this vulnerability over the network without needing any special privileges or user interaction.
• Arbitrary File Write: The Import Certificate feature allows an attacker to write arbitrary files to any location on the system.

Exploitation Methods:

• Overwriting Configuration Files: An attacker can overwrite critical configuration files such as app.ini to inject malicious settings or scripts.
• Remote Code Execution: By overwriting executable files or scripts, an attacker can achieve RCE, leading to full system compromise.

3. Affected Systems and Software Versions

Affected Software:

• Nginx-UI: Versions prior to 2.0.0.beta.12

Vendor and Product Information:

• Vendor: 0xJacky
• Product: Nginx-UI

4. Recommended Mitigation Strategies

Immediate Mitigation:

• Upgrade: Upgrade Nginx-UI to version 2.0.0.beta.12 or later, which includes the fix for this vulnerability.
• Disable Feature: Temporarily disable the Import Certificate feature until the system can be updated.

Long-Term Mitigation:

• Input Validation: Implement strict input validation to ensure that only valid certificate files are accepted.
• Access Controls: Enforce strict access controls and authentication mechanisms to limit who can use the Import Certificate feature.
• Regular Audits: Conduct regular security audits and code reviews to identify and mitigate similar vulnerabilities.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations using Nginx-UI within the European Union. Given the critical nature of the vulnerability, it could be exploited to compromise web servers, leading to data breaches, service disruptions, and potential financial losses. The high EPSS score of 5 indicates a moderate likelihood of exploitation in the wild.

Regulatory Compliance:

• GDPR: Organizations must ensure that they comply with GDPR regulations by promptly addressing the vulnerability to protect personal data.
• NIS Directive: Critical infrastructure providers must adhere to the Network and Information Systems (NIS) Directive, which mandates robust cybersecurity measures.

6. Technical Details for Security Professionals

Vulnerability Details:

• Root Cause: The Import Certificate feature in Nginx-UI does not validate the input to ensure it is a valid certificate/key, allowing arbitrary file writes.
• Affected Code:
  • api/certificate/certificate.go (Line 72)
  • internal/cert/write_file.go (Line 15)

References:

• GitHub Advisory: GHSA-xvq9-4vpv-227m
• NVD Entry: CVE-2024-23827
• Fix Commit: 8581bdd3c6f49ab345b773517ba9173fa7fc6199

Detection and Monitoring:

• Log Analysis: Monitor logs for unusual file write activities, especially in critical system directories.
• Intrusion Detection: Implement intrusion detection systems (IDS) to detect and alert on suspicious activities related to the Import Certificate feature.

Conclusion: The vulnerability in Nginx-UI is critical and requires immediate attention. Organizations should prioritize updating to the patched version and implement additional security measures to mitigate the risk of exploitation. The European cybersecurity landscape demands vigilance and proactive measures to safeguard against such high-impact vulnerabilities.