#VU61393 UNIX symbolic link following in libarchive - CVE-2021-23177

Vulnerability identifier: #VU61393

Vulnerability risk: Low

CVSSv4.0: 4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-23177

CWE-ID: CWE-61

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
libarchive
Client/Desktop applications / Software for archiving

Vendor: libarchive

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a symlink following issue when extracting files from archive, which can lean to changing ACLs of the target of the link. A local user can create a specially crafted archive, trick the victim into extracting files from it and escalate privileges on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

libarchive: 3.0 - 3.5.1

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External links
https://bugzilla.redhat.com/show_bug.cgi?id=2024245

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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