Path traversal in NPM Tar

1) Path traversal

EUVDB-ID: #VU58202

Risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-37701

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Exploit availability: No

Description

The vulnerability allows a remote attacker to overwrite arbitrary files on the system.

The vulnerability exists due to input validation error when extracting tar files that contained both a directory and a symlink with the same name as the directory, where the symlink and directory names in the archive entry used backslashes as a path separator on posix systems. A remote attacker can create a specially crafted archive and overwrite arbitrary files on the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

tar: 4.0.0 - 6.1.6

External links

http://github.com/npm/node-tar/security/advisories/GHSA-9r2w-394v-53qc

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.