CVE-2017-17671 Explained : Impact and Mitigation
Learn about CVE-2017-17671, a vulnerability in vBulletin versions up to 5.3.x on Windows allowing remote PHP code execution. Find out how to mitigate and prevent this security risk.
Remote PHP code execution vulnerability in vBulletin versions up to 5.3.x on Windows.
Understanding CVE-2017-17671
What is CVE-2017-17671?
Remote PHP code execution is possible in vBulletin versions up to 5.3.x on Windows due to a vulnerability that allows unauthenticated requests to reach a require_once call, enabling directory traversal sequences to specify any desired pathname.
The Impact of CVE-2017-17671
This vulnerability can be exploited by including directory traversal sequences to access an Apache HTTP Server log file, potentially leading to unauthorized remote code execution.
Technical Details of CVE-2017-17671
Vulnerability Description
The vulnerability arises from an oversight in blocking directory traversal sequences, allowing an attacker to send a malicious HTTP request containing PHP code and access sensitive files.
Affected Systems and Versions
- Product: vBulletin
- Versions affected: up to 5.3.x
Exploitation Mechanism
- Attackers can exploit this vulnerability by sending a crafted HTTP request with directory traversal sequences to execute arbitrary PHP code remotely.
Mitigation and Prevention
Immediate Steps to Take
- Apply vendor-supplied patches or updates to mitigate the vulnerability.
- Implement strict input validation to prevent malicious inputs.
Long-Term Security Practices
- Regularly update and patch software to address known vulnerabilities.
- Monitor and restrict network traffic to prevent unauthorized access.
Patching and Updates
- Stay informed about security updates from vBulletin and apply patches promptly to secure the system.