For security researchers that need to stay on top of emerging malware
threats the VirusTotal malware database has become an integral tool.
Anyone can upload a suspicious file to the web tool to check whether the
dozen or so antivirus engines, such as Kaspersky,McAfee, Symantec, and
others, detect it as malware. 

 The tool is meant to be used by the good guys, but as one researcher found last year, black hat hackers were also using the service to test their malware against antivirus products prior to releasing it in the wild — despite the tool’s shortcomings for comparative analysis.

While Virus Total maintains detailed information about malicious files affecting Windows, Linux malware has remained something of a blind spot for the tool, in part because such malware is much rarer.
The tool offered basic information about each Linux file sample, but lacked additional information that AV companies and researchers were given for Windows malware.

That situation might have been fine in the past. However, over the past two years, a new breed of Linux malware has emerged whose chief targets are not PCs but vulnerable web servers.

In part due to the lack of information, antivirus vendors were slow
to respond to Linux malware samples, often submitted as ELF files — the
standard binary file format for executables, object code, shared
libraries, and core dumps for Unix and Unix-like systems. As such,
detection rates by AV vendors remained low. Now the number of ELF files
submitted is rising: in the last week alone, there were over 35,000
suspicious ELF files submitted to VirusTotal, slightly less than the
44,000 suspicious Microsoft Word files uploaded.

VirusTotal announced
on Tuesday that it will be addressing the shortcomings with the web
tool for Linux malware. “Even though the popularity of the Windows OS
among average end-user systems has meant that attackers have mostly
focused on developing malware for Windows systems, ELF badness is a
growing concern,” the Google subsidiary wrote in a post on Tuesday.

Read more about this Linux malware on ZDNET