Updated Google exempts its own websites from Chrome's automatic data-scrubbing feature, allowing the ads giant to potentially track you even when you've told it not to.
Programmer Jeff Johnson noticed the unusual behavior, and this month documented the issue with screenshots. In his assessment of the situation, he noted that if you set up Chrome, on desktop at least, to automatically delete all cookies and so-called site data when you quit the browser, it deletes it all as expected – except your site data for Google.com and YouTube.com.
While cookies are typically used to identify you and store some of your online preferences when visiting websites, site data is on another level: it includes, among other things, a storage database in which a site can store personal information about you, on your computer, that can be accessed again by the site the next time you visit. Thus, while your Google and YouTube cookies may be wiped by Chrome, their site data remains on your computer, and it could, in future, be used to identify you.
Johnson noted that after he configured Chrome to wipe all cookies and site data when the application closed, everything was cleared as expected for sites like apple.com. Yet, the main Google search site and video service YouTube were allowed to keep their site data, though the cookies were gone. If Google chooses at some point to stash the equivalent of your Google cookies in the Google.com site data storage, they could be retrieved next time you visit Google, and identify you, even though you thought you'd told Chrome not to let that happen.
We're suing Google for harvesting our personal info even though we opted out of Chrome sync – netizensREAD MORE
Ultimately, it potentially allows Google, and only Google, to continue tracking Chrome users who opted for some more privacy; something that is enormously valuable to the internet goliath in delivering ads. Many users set Chrome to automatically delete cookies-and-site-data on exit for that reason – to prevent being stalked around the web – even though it often requires them to log back into websites the next time they visit due to their per-session cookies being wiped.
Yet Google appears to have granted itself an exception. The situation recalls a similar issue over location tracking, where Google continued to track people’s location through their apps even when users actively selected the option to prevent that. Google had put the real option to start location tracking under a different setting that didn’t even include the word “location.”
In this case, “Clear cookies and site data when you quit Chrome” doesn’t actually mean what it says, at least not for Google.
Just a bug?
Johnson tried to give Google the benefit of the doubt, and suggested “perhaps this is just a Google Chrome bug, not intentional behavior” though noted: “The question is why it only affects Google sites, not non-Google sites.” Site data can include cached files, we note.
This is very far from the first time that Google has been accused of storing personal information despite clear user intent. In July, it was sued by Chrome users who accusing the mega-corp of collecting personal information despite their decision not to sync data stored in Chrome with a Google Account.
"Google intentionally and unlawfully causes Chrome to record and send users’ personal information to Google regardless of whether a user elects to Sync or even has a Google account," the lawsuit stated.
And in February, it was accused of sending what looked like per-installation ID numbers to Google, which developers said could also be used to track people across the web, and which may violate Europe's General Data Protection Regulation, because the identifier could be considered to be personally identifiable data.
In response, Google insisted the numbers only included information about the variation of Chrome being used, rather than a unique fingerprint. However, shortly afterward it changed the description of the identifier and removed a section that said it “will not contain any personally identifiable information, and will only describe the state of the installation of Chrome itself,” rewriting it in impenetrable language to say instead “a subset of low entropy variations are included in network requests sent to Google. The combined state of these variations is non-identifying, since it is based on a 13-bit low entropy value.”
Google is being investigated by the US government and European Union for operating services without following its own rules and unfairly promoting its own services over those of competitors.
The search giant also announced earlier this year it was planning to kill off all third-party cookies by the end of 2021, as has already been done by Safari and Firefox. Though it will still retain first-party cookies and, it seems, give its own sites special preference in Chrome.
We asked Google for an explanation. We will update this story if it gets back to us. ®
Updated to add
A Google spokesperson has been in touch to say the issue is a programming error, and will be fixed: "We are aware of a bug in Chrome that is impacting how cookies are cleared on some first-party Google websites. We are investigating the issue, and plan to roll out a fix in the coming days."