symantec endpoint protection definitions out of date

The malware is so old that it no longer poses any threat (e.g.

It only works on a platform that is no longer supported by the AV engine, e.g.

It depends on the malware as well as the vendor, but the primary incentive for reducing the number of signatures is performance.Ī few reasons why a malware detection rule might be removed: Periodical re-scanning of the entire collection of malware is performed to check if some changes in the AV have lead to malware not being detected or false positives have been introduced by smart signatures. That means Some malware will lose specific detection although some AV engines will output the detection with multiple signatures, not just stop at the first detection. When the performance is better with the smart signature, the simple signatures will receive a lower priority or will be deleted. This smarter signature is slower than the simple byte pattern but when there are a lot of variant signatures, the overall performance will favor the smart signature. features extracted from emulating the malware, like packers, loading patterns and behavior.a combination of byte patterns and metadata about the executable.the same classical byte pattern but on something that doesn't change between variants.The AV company then starts seeing a pattern and produces a smarter signature that finds a common factor and detects all of the variants.

So variants start trickling in: Malw.1, Malw.B, Malw.X.32768. Let's say a signature is added for 'Malw' malware but then the persistent malware writer makes subtle changes to avoid that specific detection. Detection for a piece of malware is never removed from a mainstream AV.ĭetection for old or rare malware is not removed mainly because AV benchmarks and clients seeing one AV missing detection while the others have it.

Symantec endpoint protection definitions out of date