Zip Bomb Detection

Gatekeeper

A malicious actor publishes a tool package that is 48 KB compressed but inflates to 12.3 GB when extracted — filling disk and causing a denial-of-service. MPP's Gatekeeper checks the compression ratio before extracting a single byte.

com.malicious.free-tool-v1.0.0.mpp

Published 2 hours ago · 48 KB download

Looks harmless
Without MPP

Click install to begin extraction.

With MPP

Click install to run Gatekeeper checks.

Step 1 of 7 — archive safety checks

The Gatekeeper's first step checks the archive before any content is read. It streams the ZIP central directory to compute compressed vs uncompressed sizes without decompressing. If the ratio exceeds 100×, the entry count exceeds 1,000, or the total uncompressed size exceeds 256 MB, the package is refused immediately.