Description
This script is vulnerable to arbitrary file deletion.
This issue allows an attacker to influence calls to the 'unlink()' function and delete arbitrary files. Due to a lack of input validation, an attacker can supply directory traversal sequences followed by an arbitrary file name to delete specific files.
Remediation
Your script should filter metacharacters from user input.
References
Related Vulnerabilities
jQuery File Upload unauthenticated arbitrary file upload
PHP Improper Input Validation Vulnerability (CVE-2016-7417)
MyBB Improper Input Validation Vulnerability (CVE-2016-9420)
MediaWiki Improper Input Validation Vulnerability (CVE-2011-1579)
SharePoint Improper Input Validation Vulnerability (CVE-2013-0081)