Google Inc. about enhancing the mode in Chrome , which ensures that pages from different sites are processed in separate isolated processes. Site-level isolation helps protect users from attacks that may occur through third-party blocks used on a site, such as iframe embeds, or prevents data leakage through the embedding of legitimate blocks (e.g., requests to banking services where the user may be authenticated) on malicious websites.
When separating handlers bound to a domain, each process contains data from only one site, making it difficult to carry out attacks aimed at cross-site data capture. In the desktop versions of Chrome handlers bound to the domain, rather than the tab, were implemented starting with . In this mode was activated for the Android platform as well.
To reduce overhead, the site isolation mode on Android is activated only if a password login is detected on the page. Chrome remembers the use of the password and engages protection for all subsequent accesses to the site. Protection is also applied immediately for a predefined list of sites popular among mobile users. The selective activation method and added optimizations allowed memory consumption growth due to the increased number of active processes to remain at an average level of 3-5%, instead of the 10-13% observed when enabling isolation for all sites.
The new isolation mode has been activated for 99% of Chrome 77 users on Android devices equipped with at least 2 GB of RAM (for 1% of users, the mode remains disabled for performance monitoring). You can manually enable or disable the site isolation mode through the setting ‘chrome://flags/#enable-site-per-process’.
In the desktop version of Chrome, the aforementioned site isolation mode has now been enhanced to counter attacks aimed at fully compromising the content handler process. The improved isolation mode will protect site data from two additional types of threats: data leaks resulting from side-channel attacks, such as Spectre, and leaks after complete compromise of the handler process when vulnerabilities are successfully exploited that allow control over the process but are insufficient to bypass sandbox isolation. Similar protection will be added to Chrome for Android later.
The essence of the method is that the controlling process remembers which site the worker process has access to and prohibits access to other sites, even if an attacker gains control over the process and tries to access resources from another site. The restrictions cover resources related to authentication (stored passwords and Cookies), data directly loaded over the network (filtered and tied to the current site's HTML, XML, JSON, PDF, and other file types), data in internal storage (localStorage), permissions (granted site access to the microphone, etc.), and messages transmitted through the postMessage and BroadcastChannel APIs. All such resources are labeled with the source site and checked by the controlling process for the ability to transfer upon request from the worker process.
From the Chrome-related events, it is also worth noting the proposed inclusion of support for the feature in Chrome , which allows creating links to specific words or phrases without explicitly indicating labels in the document using the "a name" tag or the "id" attribute. The syntax for such links is planned to be approved as a web standard, which is still in the stage of . The transition mask (essentially a scroll search) is separated from the regular anchor by the marker ":~:". For example, when opening the link "https://opennet.ru/51702/#:~:text=Chromе", the page will shift to the position of the first mention of the word "Chromе", and this word will be highlighted. This capability has been added in the , but requires launching with the flag "—enable-blink-features=TextFragmentIdentifiers" to enable.
Another interesting upcoming change in Chrome the ability to freeze inactive tabs, allowing automatic unloading from memory of tabs that have been in the background for more than 5 minutes and are not performing meaningful actions. The decision on the suitability of a particular tab for freezing is based on heuristics. This change has been added to the Canary branch, which will form the basis of Chrome 79 release, and is enabled via the flag 'chrome://flags/#proactive-tab-freeze'.
Source: opennet.ru
