CVE-2020-36651: 
JavaScript vulnerability analysis and mitigation

A critical path traversal vulnerability was discovered in youngerheart nodeserver (CVE-2020-36651). The vulnerability affects all versions of the software and allows attackers to access files outside the intended directory through directory traversal techniques using '../' patterns. The issue was discovered and reported through the huntr bug bounty program (Huntr Report).

The vulnerability exists in the request path handling functionality where the application failed to properly sanitize user input containing '../' patterns. This allowed attackers to traverse directories and access files outside the intended directory structure. The vulnerability has a CVSS base score of 9.8 indicating critical severity (VulDB Report). The technical root cause was the lack of proper input validation and sanitization of request paths.

Successful exploitation of this vulnerability could lead to unauthorized access to sensitive files on the system, information disclosure, and potential exposure of critical system files like /etc/passwd. An attacker could traverse outside the intended directory structure to read arbitrary files accessible to the application process (Huntr Report).

The vulnerability is easily exploitable by sending HTTP requests with path traversal sequences (../) to access files outside the intended directory. A proof of concept demonstrated successful exploitation by accessing /etc/passwd using the path traversal technique (Huntr Report).

The vulnerability was fixed by implementing proper input sanitization using regex to remove '../' patterns from request paths. The fix was implemented in commit c4c0f01 which replaces all occurrences of '..' in the request path with empty strings (GitHub Commit). Users should upgrade to the patched version containing this security fix.

The vulnerability was responsibly disclosed through the huntr bug bounty program, where the researcher was awarded $25 for identifying and fixing the vulnerability. The fix was reviewed and merged by the project maintainers (Huntr Report).