The most infamous example, 42.zip , is a 42-kilobyte file that, when fully extracted, expands to 4.5 petabytes (
The ZIP algorithm can compress repetitive data (like a file filled entirely with zeros) extremely efficiently. A 10 GB file of zeros can be compressed into a few megabytes. Infinite.zip
Systems should be configured to reject archives where the ratio of compressed-to-uncompressed size is suspiciously high. The most infamous example, 42