Well based on the information in the alert, this is what is going on:
One of your firefox extensions is trying to connect to download.primawega.com and avast believs that URL to be malicious, e.g. it is on its malicious sites list.
Actions:
Check your firefox extensions, are they all ones that you have installed and why would they be trying to make a connection to that site. Any recently installed add-ons or ones that you aren't familiar with, disable them one at a time and see if you can find which add-in is responsible.
Find that i8_vW_8_b.dll file in the path given and upload it for analysis:
You could also check the offending/suspect file at:
VirusTotal - Multi engine on-line virus scanner and
report the findings here, post the URL in the Address bar of the VT results page.
Alternative scan:
If you haven't already got this software (freeware), download,
install,
update and run it and report the findings (it should product a log file).
Don't worry about reported tracking cookies they are a minor issue and not one of security, allow SAS to deal with them though. - See
http://en.wikipedia.org/wiki/HTTP_cookie.
@@@@Avast isn't alone in not liking that site,
http://www.urlvoid.com/scan/primawega.com and
http://www.mywot.com/en/scorecard/primawega.com.
