#VU61257 UNIX symbolic link following in arborist - CVE-2021-39135

Vulnerability identifier: #VU61257

Vulnerability risk: Low

CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-39135

CWE-ID: CWE-61

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
arborist
Web applications / Modules and components for CMS

Vendor: npm Inc.

Description

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

The vulnerability exists due to a symlink following issue. A local attacker can create a specially crafted symbolic link to a critical file on the system and overwrite it with privileges of the application.

Successful exploitation of this vulnerability may result in privilege escalation.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

arborist: 0.0.0 - 2.8.1

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External links
https://github.com/npm/arborist/security/advisories/GHSA-gmw6-94gg-2rc2
https://www.npmjs.com/package/@npmcli/arborist
https://www.oracle.com/security-alerts/cpuoct2021.html

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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.