YOU MAY LIKE Nmap project becomes latest victim of Google’s ‘wrongful blocking’ of cybersecurity resources That means we still load cached images when a user revisits the same site, but we don’t share those caches across sites.”

“To prevent this possibility, Firefox 85 uses a different image cache for every website a user visits. Mozilla wrote: “Unfortunately, some trackers have found ways to abuse these shared resources to follow users around the web. Previously, Firefox initially loaded website images from the network, but if the same image was used on subsequent websites visited, it loaded the image from the browser’s local image cache rather than reloading from the network.

Mozilla cited an example of how the changes will work in practice, pointing to changes in Firefox’s image cache. This applies to all third-party resources embedded on a website, regardless of whether Firefox considers that resource to have loaded from a tracking domain. To further protect users from connection-based tracking, Firefox 85 also partitions pooled connections, prefetch connections, preconnect connections, speculative connections, and TLS session identifiers.” This will “greatly reduce the effectiveness” of cache-based supercookies by stopping a tracker from using them across websites, adds Mozilla.įirefox 85 partitions all of the following caches by the top-level site being visited: HTTP cache, image cache, favicon cache, HSTS cache, OCSP cache, style sheet cache, font cache, DNS cache, HTTP Authentication cache, Alt-Svc cache, and TLS certificate cache. The latest update to the Mozilla browser will therefore now partition network connections and caches, isolating them to the website they were created on. Read more of the latest browser security news “This makes it nearly impossible for users to protect their privacy as they browse the web,” says Mozilla in a blog post. However, supercookies are much more difficult to delete and block. Like ordinary cookies, supercookies are small pieces of data stored on a computer by a web browser that can track a user’s internet footprint and remember information such as payment details or items in a shopping basket.

Updates to Mozilla browser include protections against hard-to-block cross-site trackersįirefox 85 has cracked down on so-called ‘supercookies’ by introducing cache partitioning that blocks cross-site tracking.

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