The file is structured like a "nesting doll." Inside the main ZIP file are 16 smaller ZIP files. Inside each of those are 16 more, and so on.
Most modern operating systems and security software have evolved to neutralize threats like "nickel.zip":
: When a user or a server-side process attempts to decompress "nickel.zip," the system's hard drive space is instantly filled, and the CPU reaches 100% utilization.
: 42.zip was a 42-kilobyte file that expanded to 4.5 petabytes (4,503,599,627,370,496 bytes) of data.
: If the software detects that a 1MB file is trying to expand into 1GB, it will flag the file as a "Decompression Bomb" and halt the process.
: If a file has 5 layers of recursion, and each layer contains 16 files, the final count of files to be processed is
: By "distracting" the antivirus scanner with the massive decompression task, other real malware may sneak past the scanner while the system is bogged down. 4. Modern Defenses
: In a corporate environment, sending a zip bomb to a server that automatically scans attachments can take the entire mail server offline.