CVE-2017-5384 : Exploit Details and Defense Strategies
Learn about CVE-2017-5384 affecting Firefox < 51, exposing sensitive data via Proxy Auto-Config files. Find mitigation steps and update recommendations here.
This CVE-2017-5384 article provides insights into a security vulnerability affecting Firefox versions older than 51, related to Proxy Auto-Config files and information disclosure.
Understanding CVE-2017-5384
What is CVE-2017-5384?
Proxy Auto-Config (PAC) files in Firefox versions prior to 51 can expose sensitive information due to a JavaScript function that is called for all URL requests, potentially leading to security risks.
The Impact of CVE-2017-5384
The vulnerability allows remote retrieval of PAC files when Web Proxy Auto Detect (WPAD) is enabled, compromising user data confidentiality.
Technical Details of CVE-2017-5384
Vulnerability Description
- PAC files can execute a JavaScript function for all URL requests, revealing more details than shared with the proxy, especially in HTTPS scenarios.
Affected Systems and Versions
- Product: Firefox
- Vendor: Mozilla
- Versions Affected: < 51
Exploitation Mechanism
- Enabling WPAD allows remote access to PAC files, potentially leading to information disclosure.
Mitigation and Prevention
Immediate Steps to Take
- Disable WPAD in browser settings to prevent remote retrieval of PAC files.
- Regularly monitor security advisories from Mozilla for updates.
Long-Term Security Practices
- Educate users on the risks of enabling WPAD and the importance of secure browsing practices.
- Implement network-level controls to restrict PAC file access.
Patching and Updates
- Update Firefox to versions 51 and above to mitigate the vulnerability and enhance security.