: 42.zip was a 42-kilobyte file that expanded to 4.5 petabytes (4,503,599,627,370,496 bytes) of data.

: Antivirus software and automated scripts often try to "peek" inside archives to scan for viruses. A zip bomb forces these scanners to keep diving deeper into layers, eventually consuming all available RAM and CPU cycles. B. Identical Data Compression

: 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.

Compression algorithms like work by finding repetitive patterns. If a file contains nothing but the same character (e.g., the letter "a") repeated a trillion times, the algorithm can compress it down to almost nothing.

: Scanners are now programmed to stop looking after a certain number of layers (e.g., 5 or 10 deep).

Most modern operating systems and security software have evolved to neutralize threats like "nickel.zip":

: 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