The most recent full new model of Firefox is out, marking the primary of two “month-to-month” upgrades you’ll see this month.
Simply as there will likely be a blue moon in August 2023 (that’s the identify utilized to a second full moon in the identical calendar month, reasonably than reference to an atmospheric phenomenon that makes the moon appear blue, in case you ever puzzled), there will likely be a blue Firefox too.
Firefox model upgrades occur each 28 days, reasonably than as soon as a month, so every time a launch comes out early sufficient within the month, there will likely be a second improve squeezed in on the finish.
Teachable moments
Happily there are not any zero-day vulnerabilities this time, however the next bug studies caught our eye:
- CVE-2023-4045: Offscreen Canvas might have bypassed cross-origin restrictions. One webpage might peek at pictures displayed in one other web page from a unique website. The identical-origin coverage in browsers is meant to limit the attain of HTML and JavaScript content material from website X so it will possibly entry types, knowledge, pictures, cookies and the like provided that they too initially got here from website X. Any methods that may bypass this same-origin safety can theoretically be used to slurp up so-called cross-origin knowledge that shouldn’t be accessible in any respect.
- CVE-2023-4047: Potential permissions request bypass through clickjacking. A rogue web page might tempt you to click on on a carefully-placed merchandise, resembling a completely innocent-looking button, just for the enter to register as a click on in a safety dialog that didn’t pop up in time so that you can see. Doubtlessly dangerous permissions, resembling accessing your location, sending notifications, activating the microphone and so forth, are usually not alleged to be granted till you’ve seen and acted on a transparent warning from the browser itself.
- CVE-2023-4048: Crash in DOMParser resulting from out-of-memory circumstances. DOM is brief for doc object mannequin, and the DOMParser is the code that deconstructs the HTML in an internet web page that the browser is rendering for show, turning it into a giant JavaScript knowledge object wherein all the person parts resembling paragraphs, headings, pictures, desk objects and so forth might be accessed and modified programmatically. Complicated pages sometimes flip into giant JavaScript buildings that may take quite a lot of reminiscence to determine after which to retailer. Assume {that a} decided attacker might intentionally eat up reminiscence by loading numerous giant however harmless pages, after which predictably set off a crash utilizing a crafted HTML file that will get fetched at simply the fallacious time.
- CVE-2023-4050: Stack buffer overflow in StorageManager. That is an old-school stack overflow that doesn’t get detected in time by Firefox itself, and will subsequently result in a crash as a substitute of a managed shutdown. All crashes brought on by the inaccurate stream of execution in a program (resembling leaping to any invalid reminiscence handle X) must be thought-about doubtlessly exploitable. Assume {that a} decided attacker might determine methods to affect the worth of X, and thereby acquire a minimum of some measure of malevolent management over the crash.
- CVE-2023-4051: Full display screen notification obscured by file open dialog. Fullscreen mode is all the time a bit dangerous, as a result of it offers the online web page you’re viewing exact management over each pixel on the display screen. Which means there are not any elements of the show that may be modified solely by the browser itself or solely by the working system. That’s why browsers goal to warn you earlier than giving over the entire show to an internet web page, so you recognize that popups that seem like official browser or working system dialogs could be no such factor.
- CVE-2023-4057 and CVE-2023-4058: Reminiscence security bugs mounted in numerous Firefox variations. As normal, though none of those bugs was clearly exploitable, and so they have been mounted proactively anyway, Mozilla has rated them “Excessive” and given its ever-frank evaluation that “we presume that with sufficient effort a few of these might have been exploited to run arbitrary code.”
What to do?
The brand new variations you might be on the lookout for after updating are:
- Firefox 116 in case you’re on the most recent model.
- Firefox ESR 115.1 if you’re a consumer of the Prolonged Assist Launch, which incorporates safety patches however doesn’t add new options. (Including 115+1 from the ESR model quantity tells you that this launch aligns with Firefox 116 for safety fixes, though its characteristic set aligns with Firefox 115.)
- Thunderbird 115.1 in case you use Mozilla’s e mail software program, which incorporates the Firefox internet looking code for rendering HTML emails and viewing emailed internet hyperlinks.
Head to Firefox -> About Firefox when you’ve got a Mac, or Assist -> About Firefox on different platforms.
Dont neglect, in case you use one of many BSDs or a Linux distro, that your Firefox launch could be managed by the distro itself, so test along with your supplier for updates.