I found out about Dasient via the presentation they did at Google (which you can see embedded below). Their angle seems to be (although this probably will change – them being a young company) that: we check your rating at Google / McAfee / Symantec and if they say that you are bad, we will find the pages which are bad and “fix” them for you (by removing the malicious code).

What bothers me:

• The blacklist approach – this means that there will be a lag before new attacks are detected
• Relying on third-party service (like the Google Safe Browsing API, McAfee SiteAdvisor, etc). While the Google Safe Browsing API has an explicit TOS stating that you can use it (under certain circumstances of course), the situation with McAfee and Symantec is not as clear-cut. Does Dasient have a contract with them or are they just scraping their websites? What if McAfee / Symantec decides that enough is enough and blocks them or even worse, sues them? Also, relying on these services means further delay in detecting the infected sites (because they must wait until these providers detect the infection)
• Their touted “dynamic filtering” technology seems to be over engineered for me. It also (as far as I understand) can’t handle situations like “the request is directed to a different machine” or “the machine is rootkitted and the malicious code is added on-the-fly”, both of these being situations which occurred in the real world (the first with CN CERT and the second with a bunch of compromised Linux machines)
• Also, I fear that because this filtering masks the problem (much like a WAF does), it will encourage people to be complacent about fixing the root of the problem (“so what if we get compromised twice a day due to weak passwords? we just click the checkbox!”)
• Finally, the prices seem a little steep to me (starting from ~10 USD a month and going over ~ 50 USD per month)

All in all it doesn’t seem to me to be worth 2M USD (which they claim to have in funding)…