Disclosure: I work for an AV vendor. Mine was one of them listed that does scan within RAR files regardless of a hidden attribute. One of the things about scan

Disclosure: I work for an AV vendor. Mine was one of them listed that does scan within RAR files regardless of a hidden attribute. One of the things about scanning within archive files is that it's quite IO intensive and by default isn't enabled for most AV installs. I very much doubt the reason for why it's stressful from an IO perspective is lost on HN readers, but one thing that is overlooked in the comments and the article itself is that by default most operating systems do not support RAR compression and really what is mainstream is ZIP on Windows, and Tarballs and Stuffit files on Mac. The default settings in most AV software are good enough for situations as the author wrote, even if they're on the list that didn't successfully scan within the archive. If your scanner is scanning on write, extracting the archive will in fact cause it to trip regardless of the file's hidden or lack there of attribute. RAR is a notable exception as it does have the ability to execute code as it is processed through a virtual machine, but at the same time a number of AV engines are geared towards situations like this using things like suspicious behaviour detection and whatnot. Those however are not necessarily enabled by default. I think that the author's beliefs are a bit overblown here. What really matters is what happens after the RAR file is extracted, not while it's more or less safely packed inside.