Staying safe online requires a healthy dose of skepticism. If a "viral pack" seems too good to be true or comes from a source with a poor reputation, it is best to stay away.
Many "packs" found on these sites are unauthorized collections of content created by others. The Dangers of .rar Files from Untrusted Sources
If you have already downloaded a file, do not open it. Run it through a reputable malware scanner or an online tool like VirusTotal before extraction.