When we went digging through our archive for related samples of malware, we were surprised to find that we already had samples of Flame, dating back to 2010 and 2011, that we were unaware we possessed. They had come through automated reporting mechanisms, but had never been flagged by the system as something we should examine closely. Researchers at other antivirus firms have found evidence that they received samples of the malware even earlier than this, indicating that the malware was older than 2010.
What this means is that all of us had missed detecting this malware for two years, or more. That’s a failure for our company, and for the antivirus industry in general.
It wasn’t the first time this has happened, either. Stuxnet went undetected for more than a year after it was unleashed in the wild, and was only discovered after an antivirus firm in Belarus was called in to look at machines in Iran that were having problems. When researchers dug back through their archives for anything similar to Stuxnet, they found that a zero-day exploit that was used in Stuxnet had been used before with another piece of malware, but had never been noticed at the time. A related malware called DuQu also went undetected by antivirus firms for over a year.
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