Google Safebrowsing

why google say this about avast.com “Yes, this site has hosted malicious software over the past 90 days”(http://www.google.com/safebrowsing/diagnostic?site=avast.com)

Report 2011-09-25 18:22:04 (GMT 1)
Website avast.com
Domain Hash 178c8b444e8def52807e7db3f63dc26e
IP Address 46.4.66.143 [SCAN]
IP Hostname a542he.avast.com
IP Country – (–)
AS Number 24940
AS Name HETZNER-AS Hetzner Online AG RZ
Detections 0 / 23 (0 %)
Status CLEAN

Report 2011-09-25 19:27:33 (GMT 1)
IP Address 46.4.66.143
IP Hostname a542he.avast.com
IP Country –
AS Number N/A
AS Name N/A
Detections 0 / 26 (0 %)
Status CLEAN

Sucuri:
web site: avast.com
status: Verified Clean
web trust: Not Blacklisted

[size=10pt][b]Google Safe Browsing Makes the Innocent Look Guilty[/b][/size]
[url=https://www.pcworld.com/businesscenter/article/192808/google_safe_browsing_makes_the_innocent_look_guilty.html] https://www.pcworld.com/businesscenter/article/192808/google_safe_browsing_makes_the_innocent_look_guilty.html[/url]

http://3.bp.blogspot.com/-kdZZ1jMZ7tw/Tn9oNWL44bI/AAAAAAAAAGE/tnVcyABR6VM/s1600/Google+Disagnotics+of+Google+Search+Site.gif

http://1.bp.blogspot.com/-XNs7jVYqxaQ/Tn9s3EYR3xI/AAAAAAAAAGM/nx54UKyKByU/s1600/Avast+Forum+URL+Void+Scan.gif