what is the purpose of scanning text files and image files which do not spread any virus.
http://www.mcafee.com/us/mcafee-labs/resources/threats-faq.aspx#6
6. Can JPEG, GIF, and other image files be infected?
Yes. Some software programs have vulnerabilities that contaminate JPEG files with malicious code. Contaminated JPEG files can carry or launch a virus, worm, or Trojan on unpatched systems.
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