The ASM is possible verify the format file?

ASM can't distinguish between file types in most cases, with the exception being the sensitive data feature. What it can do is tell the difference between binary/non-binary content being uploaded.

What you might be able to do (if you are checking Requests, that is) is enable the ICAP forwarding capability, and pass the file to a service which can evaluate the format of an uploaded object, and then let the ASM know if the file violates it's stated type. Note that the examining service will have to tell the ASM that a virus has been detected, if a file differs from it's stated type, since we are re-purposing an ASM feature.