#VU58202 Path traversal in tar - CVE-2021-37701

Vulnerability identifier: #VU58202

Vulnerability risk: Medium

CVSSv4.0: 2.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-37701

CWE-ID: CWE-22

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
tar
Web applications / JS libraries

Vendor: npm Inc.

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

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

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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.