I.   Background

The libarchive(3) library provides a flexible interface for reading and
writing streaming archive files such as tar(1) and cpio(1), and has been the
basis for the FreeBSD implementation of the tar(1) and cpio(1) utilities
since FreeBSD 5.3.

II.  Problem Description

An integer overflow in the archive_read_format_rar_seek_data() function may
lead to a double free problem.

III. Impact

Exploiting a double free vulnerability can cause memory corruption.  This in
turn could enable a threat actor to execute arbitrary code.  It might also
result in denial of service.

https://www.freebsd.org/security/advisories/FreeBSD-SA-25:07.libarchive.asc