Chrome now warns users of sites likely to serve up software that changes the home page or displays advertisements without approval.
Google has added an early warning alert to Chrome that pops up when users try to access a website that the search giant suspects will try to dupe users into downloading underhanded software.
The new alert pops up in Chrome when a user aims the browser at a suspect site but before the domain is displayed. "The site ahead contains harmful programs," the warning states.
Google emphasized tricksters that "harm your browsing experience," and cited those that silently change the home page or drop unwanted ads onto pages in the warning's text.
The company has long focused on those categories, and for obvious, if unstated, reasons. It would prefer that people -- much less, shifty software -- not alter the Chrome home page, which features the Google search engine, the Mountain View, Calif. firm's primary revenue generator. Likewise, the last thing Google wants is to have adware, especially the most irritating, turn off everyone to all online advertising.
The new alert is only the latest in a line of warnings and more draconian moves Google has made since mid-2011, when the browser began blocking malware downloads. Google has gradually enhanced Chrome's alert feature by expanding the download warnings to detect a wider range of malicious or deceitful programs, and using more assertive language in the alerts.
In January 2014, for example, Chrome 32 added threats that posed as legitimate software and monkeyed with the browser's settings to the unwanted list.
The browser's malware blocking and suspect site warnings come from Google's Safe Browsing API (application programming interface) and service; Apple's Safari and Mozilla's Firefox also access parts of the API to warn their users of potentially dangerous websites.
Google's malware blocking typically tests much better than Safari's or Firefox's, however, because Google also relies on other technologies, including reputation ranking, to bolster Chrome's Safe Browsing.
Like the Microsoft application reputation ranking used in Internet Explorer, Google's technology combines whitelists, blacklists and algorithms to create a ranking of the probability that a download is legitimate software. Files that don't meet a set legitimacy bar trigger a warning.
Google uses other signals, the details of which it has not disclosed, to identify websites that will likely serve up unwanted software like home page changers. Google search uses similar signals to ward off entries in the results list. "This change reduces the chances you'll visit these sites via our search results," wrote Lucas Ballard, a software engineer, in a Monday blog post.
Chrome 40, the browser's current most-polished version, can be downloaded for Windows, OS X and Linux from Google's website.
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