Why did crypters get caught by antivirus software

why? antivirus are able to catch them well it’s sample because it’s get scan by various AV companies and that make the crypter UD, many crypter authors will provide frequent updates to the crypter software, in the form of stub files. These contain the latest methods or algorithms used to augment the malware passed through to it, in an attempt to stay ahead of Anti-Virus companies detecting their methods, for example virustotal.com 4 will send every file you scan to AV companies, if you want to stay (FUD) for long time, then you will need an AV scanner that not distribute the samples.

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