Which attack gives unauthorized access to files on the web server?

DHCP snooping is a security feature on network switches to prevent rogue DHCP servers and enforce client-server relationships, not an attack method for accessing server files.

A path traversal attack (also known as directory traversal) allows an attacker to access files or directories that are stored outside the web root folder. By manipulating file paths with sequences like "../", attackers can trick the application into accessing arbitrary files on the server, potentially leading to unauthorized file viewing or execution.

A broadcast storm is a network phenomenon where excessive broadcast traffic consumes network bandwidth, leading to performance degradation or network collapse, not unauthorized file access.

A distributed DoS (DDoS) attack aims to disrupt service by overwhelming a target with traffic from multiple sources, not to gain unauthorized access to specific files.