Privilege escalation via prototype pollution

Prototype pollution in Async before 2.6.4 and 3.x before 3.2.2 allows remote attackers to obtain privileges via mapValues(). The createObjectIterator function used by mapValues() copies attacker-controlled proto properties into result objects, changing their prototype and enabling privilege checks or other security-sensitive logic to be subverted. Exploitation requires a caller to pass attacker-influenced object keys to mapValues(); resulting impact can include privilege escalation and, in affected applications, further integrity, confidentiality, or availability compromise.