Google Safe Browsing


Google Safe Browsing is a blacklist service provided by Google that provides lists of URLs for web resources that contain malware or phishing content. The Google Chrome, Safari, Firefox, Vivaldi, and GNOME Web browsers use the lists from the Google Safe Browsing service for checking pages against potential threats. Google also provides a public API for the service.
Google also provides information to Internet service providers, by sending e-mail alerts to autonomous system operators regarding threats hosted on their networks.
According to Google, as of September 2017, over 3 billion Internet devices are protected by this service. Alternatives are offered by both Tencent and Yandex.

Clients protected

Google maintains the Safe Browsing Lookup API, which has a privacy drawback: "The URLs to be looked up are not hashed so the server knows which URLs the API users have looked up". The Safe Browsing Update API, on the other hand, compares 32-bit hash prefixes of the URL to preserve privacy. The Chrome, Firefox and Safari browsers use the latter.
Safe Browsing also stores a mandatory preferences cookie on the computer.
Google Safe Browsing "conducts client-side checks. If a website looks suspicious, it sends a subset of likely phishing and social engineering terms found on the page to Google to obtain additional information available from Google's servers on whether the website should be considered malicious". Logs, "including an IP address and one or more cookies" are kept for two weeks. They are "tied to the other Safe Browsing requests made from the same device."

Criticism

Websites not containing malware have been blacklisted by Google Safe Browsing due to the presence of infected ads. Requesting removal from the blacklist requires the webmaster to create a Google Webmaster's Tool account and wait several days for removal to be in effect.