In the watering-hole attacks, threat actors infected two websites, cabinet.gov[.]mn and mfa.gov[.]mn, which belong to Mongolia's Cabinet and Ministry of Foreign Affairs. They then injected code to exploit known flaws in iOS and Chrome on Android, with the ultimate goal of hijacking website visitors' devices.
Definitions:
Watering hole is a computer attack strategy in which an attacker guesses or observes which websites an organization often uses and infects one or more of them with malware. Eventually, some member of the targeted group will become infected.
-Wikipedia
Whereas zero-days are a class of vulnerability that is unknown to a software developer or hardware manufacturer, an N-day is a flaw that is already publicly known but may or may not have a security patch available.
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