#VU62361 Prototype pollution in Async - CVE-2021-43138

Vulnerability identifier: #VU62361

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-43138

CWE-ID: CWE-94

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Async
Web applications / JS libraries

Vendor: Caolan McMahon

Description

The vulnerability allows a remote attacker to escalate privileges within the application.

The vulnerability exists due to improper input validation when handling data passed via the mapValues() method. A remote attacker can send a specially crafted request and escalate privileges within the application.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Async: 2.0.0 - 2.0.1, 2.1.0 - 2.1.5, 2.2.0, 2.3.0, 2.4.0 - 2.4.1, 2.5.0, 2.6.0 - 2.6.3, 3.0.0 - 3.0.1, 3.1.0 - 3.1.1, 3.2.0 - 3.2.2

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External links
https://github.com/advisories/GHSA-fwr7-v2mv-hh25

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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.