Unzipper::unzip extracts each archive entry to a path built from the entry's raw, attacker-controlled name without any traversal check. A ZIP archive whose entry names contain ../ components (or an absolute path) can therefore cause files to be written outside the destination directory chosen by the caller — a "zip-slip" / directory-traversal arbitrary file write (CWE-22 / CWE-23 / CWE-36).

All published versions are affected. unzip has only ever released 0.1.0 (published 2017-12-23) and appears unmaintained, so no fixed version is available.

A malicious archive with a single entry named ../ESCAPED.txt extracted via Unzipper::unzip writes ESCAPED.txt one level above the destination directory.