UnZip: User-assisted execution of arbitrary code

Background

Info-ZIP’s UnZip is a tool to list and extract files inside PKZIP compressed files.

Description

Tavis Ormandy of the Google Security Team discovered that the NEEDBITS macro in the inflate_dynamic() function in the file inflate.c can be invoked using invalid buffers, which can lead to a double free.

Impact

Remote attackers could entice a user or automated system to open a specially crafted ZIP file that might lead to the execution of arbitrary code or a Denial of Service.

Workaround

There is no known workaround at this time.

Resolution

All UnZip users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=app-arch/unzip-5.52-r2"