So, I decided to install league on my sandbox machine where I do my non work related projects, and I came across a fairly glaring vulnerability, mostly because the client is REALLY bad at cleaning up after itself, unacceptably so, for how large of a company Riot games is.
When a new version of the Client is installed, the changes trigger the need for additional firewall safety permissions, and that WIndows recognizes this as a distinct application. This isn't an issue, except that League leaves behind all of its previous versions, the firewall rules, the registry entries, the installation privileges. Unless a user is dilligent enough to go through cleaning out their application registry and their firewall every so often, this leaves a massive vulnerability. Malware can easily assume the visage of a no longer existent application, running about under the cowl of improper uninstalls.
The league client seriously needs an upgrade in its uninstalling capabilities, so that it doesn't leave multiple redundant records, registry entries, and firewall rules just laying about on the users machine.