Single Letter Malware (Unix Executable) File

In the last week or I so, I have started getting messages about a file that might be a virus po-up screen. The file listed is always a single letter and the message indicates that the download date is unknown. When I look at the file, it just says that it's a Unix executable and is usually between 300K - 400K in size. When it first started happening, I did not pay attention and just sent the file to the trash and emptied it out. Now I'm thinking I may have some sort of virus or malware on my system. Any suggestions or has anyone else seen this before? Today's file name is just the letter 'p'. But in the past it's been 'r' or 's' or some other random letter. Screen shot of the info for the file below -