CVE-2021-43138: High severity async vulnerability

A vulnerability exists in Async through 3.2.1 for 3.x and through 2.6.3 for 2.x (fixed in 3.2.2 and 2.6.4), which could let a malicious user obtain privileges via the mapValues() method.

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

— Red Hat

A vulnerability was found in the async package. This flaw allows a malicious user to obtain privileges via the mapValues() method.

Async could allow a remote attacker to execute arbitrary code on the system, caused by prototype pollution in the mapValues() method. By persuading a victim to open a specially-crafted file, an attacker could exploit this vulnerability to execute arbitrary code on the system.

— IBM

In Async before 2.6.4 and 3.x before 3.2.2, a malicious user can obtain privileges via the mapValues() method, aka lib/internal/iterator.js createObjectIterator prototype pollution.