An extract from Brian Krebs last blog post.

I have often recommended file-scanning services like VirusTotal and Jotti, which allow visitors to upload a suspicious file and scan it against dozens of commercial anti-virus tools. If a scan generates any virus alerts or red flags, the report produced by the scan is shared with all of the participating anti-virus makers so that those vendors can incorporate detection for the newly discovered malware into their products.

That pooling of intelligence on new threats also serves to make the free scanning services less attractive to virus authors, who would almost certainly like nothing more than to freely and simultaneously test the stealth of their new creations across a wide range of security software. Still, there is nothing to stop an enterprising hacker from purchasing a license for each of the anti-virus tools on the market and selling access to a separate scanning service that appeals to the virus-writing community.

Enter upstart file-scanning services like av-check.com and virtest.com, which bank on the guarantee that they won’t share your results with the anti-virus community.

For $1 per file scanned (or a $40 monthly membership) av-check.com will see if your file is detected by any of 22 anti-virus products, including AVAST, AVG, Avira, BitDefender, NOD32, F-Secure, Kaspersky, McAfee, Panda, Sophos, Symantec, and Trend Micro. “Each of them is setten [sic] up on max heuristic check level,” av-check promises. “We guarantee that we don’t save your uploaded files and they are deleted immediately after the check. Also , we don’t resend your uploaded files to the 3rd person. Files are being checked only locally (without checking/using on other servers.” In other words: There is no danger that the results of these scans will somehow leak out to the anti-virus vendors.

Read the full post here.