Ensuring user-provided filenames don't contain path sequences.
The /root directory, particularly in Linux systems, is the home directory for the root user. Files and directories within /root are critical for system administration and security. -include-..-2F..-2F..-2F..-2Froot-2F
../../../../../root/
: Modern WAFs are designed to detect and block common attack patterns, including URL-encoded traversal sequences like -2F..-2F . Conclusion particularly in Linux systems
: Instead of building paths manually, use filesystem APIs that resolve paths and ensure they remain within a specific "base" directory (e.g., realpath() in PHP or path.resolve() in Node.js). -include-..-2F..-2F..-2F..-2Froot-2F