CVE-2018-20990

HIGH7.5EPSS 0.30%

Links in archives can overwrite any existing file

Published: 8/25/2021Modified: 11/8/2023
Also known as:GHSA-2367-c296-3mp2RUSTSEC-2018-0002

Description

When unpacking a tarball with the `unpack_in`-family of functions it's intended that only files within the specified directory are able to be written. Tarballs with hard links or symlinks, however, can be used to overwrite any file on the filesystem. Tarballs can contain multiple entries for the same file. A tarball which first contains an entry for a hard link or symlink pointing to any file on the filesystem will have the link created, and then afterwards if the same file is listed in the tarball the hard link will be rewritten and any file can be rewritten on the filesystem. This has been fixed in https://github.com/alexcrichton/tar-rs/pull/156 and is published as `tar` 0.4.16. Thanks to Max Justicz for discovering this and emailing about the issue!

Affected packages (2)

CVSS scores

SourceVersionSeverityVector
osvCVSS 3.1HIGH7.5CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References (6)