https of certain cookies get reported to be dangerous by Avast

https of certain cookies get reported to be dangerous by Avast:

The “dangerous” cookie that gets mostly reported is: http://cdn1.ads.contentabc.com/ads/desig… = cdn1.ads.contentabc.com

I blocked the possibility of this website for loading graphical contents via my Firefox browser. A few other https of (internet casino) websites also got reported by Avast - but never appeared again after I blocked their graphics in my Firefox browswer, yet I ask myself: Why does http://cdn1.ads.contentabc.com/ads/desig… always gets reported by Avast again?

This is a screenshot of the avast notification:

Infektionsdetails
URL: http://cdn1.ads.contentabc.com/ads/desig
Prozess: C:\Program Files\Mozilla Firefox\firefox…
Infektion: URL:Mal

In the SAME notification Avast also always assures that I was successfully protected against the malware.

The malware appears when I’m surfing on Redtube pages, I sent a mail to Redtube wherein I described the whole problem - but the Redtube customer service replied via email that their website is allegedly NOT infected by malware or viruses, their McAffee program would have found nothing. I had always doubts in the past whether McAffee is a reliable malware scanning program at all + always refused to buy or use this software…

So far no damage happened to my computer’s software/hardware but I’m a bit irritated why these Avast reports always appear again, almost exclusively when I’m on Redtube.

Can anyone inform me what I should do to get rid of this irritating phenomenon?

Thanks

URLVoid
http://www.urlvoid.com/scan/cdn1.ads.contentabc.com/

hpHosts list it as ATS http://hosts-file.net/?s=cdn1.ads.contentabc.com

•ATS - Ad/tracking servers This classification is assigned for domains being used for advert or tracking purposes

See: cdn1.ads.contentabc.com
Unable to properly scan your site. Site returning error (40x): HTTP/1.1 403 Forbidden
Hostname: cdn1.ads.contentabc.com
IP address: 8.27.247.125 used for advert or tracking purposes Site not found on 198.78.197.126 var GTS_POP_Block malware logged
(GTS_POP_URL=GTSAdsPU.getOpenXURL)vuln test/chatJS.php?name=test → noshade footprint
AS info AS Name: LEVEL3 Level 3 Communications

IPs allocated: 78323968

Blacklisted URLs: 417

Hosts…

…malicious URLs? Yes

…badware? Yes

…botnet C&C servers? No

…exploit servers? Yes

…Zeus botnet servers? No

…Current Events? Yes

polonus