A zero-day vulnerability allowed potential attackers to register domains using Latin homoglyph characters. The domains could be used in insider, phishing, and social-engineering attacks against organizations. Only Verisign and Amazon (S3) have remediated this issue. The issue was discovered by Soluble security researcher Matt Hamilton in collaboration with security testing firm Bishop Fox. The .. (Voiced Velar Stop) is the most convincing character near indistinguishable from its Latin counterpart.
Source: https://www.bleepingcomputer.com/news/security/zero-day-bug-allowed-attackers-to-register-malicious-domains/