Symantec Patents Multiple File Area Virus Scanning

DigitumDei writes "Symantec announced on Wednesday that it has aquired a new patent (United States Patent - 6,851,057) titled "Data driven detection of viruses". Symantec has declined to comment on whether it will pursue litigation. Symantec's director of intellectual property Michael Schallop stated : 'We don't generally discuss how we will leverage this patent against competitors or others,'." From the article: "[The patent] could refer to any technology that allows antivirus researchers or antivirus products to use scripting to determine, dynamically, where in a file to scan and detect threats. It could also include the use of Javascript or other common scripting languages to direct antivirus scanning..."

Comments

Lots of prior art on this patent

[oldfogie]

FWIW, I am an (ex-)anti-virus author, and I actually looked at this patent.

First, the person who wrote the text should be shot... it's worded to be as confusing as possible, so that even an expert in the field can't readily tell what is being covered in the patent.

Next, from what I can tell, the patent seems to cover 3 main points (in various flavors, to come up with their 20 points):

1) We don't just scan for strings, we take into consieration what sort of virus it might be, and only scan in the appropriate place.

2) We have a "scripting language" that can direct the virus scan.

3) We can emulate a "virus target" and see if the virus goes for it.

All of these points were done years ago. The first two points were "state of the art" as of 1990. The product I worked on (name withheld for various reasons. Sorry about that...) was, at the time, unlike the other virus scanners out there. It used "precision scanning" in which the nature of the virus being scanned for was taken into account, and was scanned for ONLY AT THE LOCATION AT WHICH THE INFECTION WOULD OCCUR. This was a major differentiation from the "bulk scanners" (i.e. run the entire file through a string filter that contains all virus signatures, and see if there are any matches. As a trivia note, "bulk scanners" are why all anti-virus scanners use encrypted (in some trivial way) virus signatures -- so that a virus scanner would not be identified as an infected file by another virus scanner, or even by itself!) that all other major anti-virus vendors used.

Also, the virus scanner I wrote included a scripting language so that users could add their own virus scan and remove definitions.

As for emulating a virus target and seeing if the virus "bites", that is also old hat. While a commercial product was never introduced, a lab prototype was publically demonstrated in 1996, in which files under examination were interpreted in a virtual 80x86 environment, including OS and file system, both to see if they did anything suspicious, and to see if they "tagged along" on "provocative" system calls.

And, yes, I still have my old code sitting around. It would be a pity if someone suddenly showed it to Symantec or the patent office...