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A zero-day attack is a successful attempt by hackers to exploit software and network vulnerabilities that were previously unknown. Softwares and network security systems have vulnerabilities and a weak point that act as a backdoor or a window for the hackers to launch a full-scale attack. The developers can develop a patch in response to an attack but is helpless if an attack has already occurred. Zero-day exploits are highly valued bug bounty programs and fetch a good rate in the underground market as these attacks cause significant damage for a prolonged period.