VX-underground is one of the largest collection of malware source code, samples, and papers on the internet and you can access all of them at free of cost over here https://www.vx-underground.org/ and twitter profile is at @vxundergound where you can get the latest updates about any malware samples.
The one frequently asked as well as often repeated question to the vxunderground twitter site is what’s the password of the malware samples. The answer is simple and the password is “infected”. It can be readily found on their twitter profile!
If you have any questions about VX-underground then they can be reached here – [email protected]! They have some cool folks on Twitter!