Discussion
Not sure who needs to know this, but if you download and install the Windows version of Rufus, the free software for writing ISO images to USB/CD-ROM, your PC will end up with about 100 trojans.
Edit: The site I downloaded from was rufus[.]ie which is apparently the official site. During installation, the software threw up a couple of rather verbose messages saying it needed to download additional components.
@galaxis yes if you trust WindowsDefender to defend you against this attack you will be sorely mistaken. It successfully detects all the malware installed, but it acts weird and sends notifications about malware detections even though its own interface says a scan is clean.
@briankrebs ventoy is better. Boot the iso you want from a menu.
A kind reader submitted the Rufus installer to any.run, a sandbox which walks through the installation of software to find malware that gets installed only *AFTER* the executable is clicked. You can see exactly all of the post-install prompts to download additional software that I also saw.
@briankrebs This really looks like a malvertising campaign to me. Rufus doesn't even have an installer. You just run it directly.
I found ads on the rufus.ie site pointing to get-blazer.com, which is a known malware host.
https://any.run/report/2744d66eaf61f28d1930ae45562f9f4cd1b33db4083a1dcaca8a5d6703846282/67191634-20ef-49a1-ae63-bc194b618be1
@briankrebs@infosec.exchange the scary boxes like, downloading from the MS github and checking for its own updates, which is opt in? what the hell even is this alarmist thread
@amy alarmist? trigger much?
@demon6 wait, what? how is this related? I'm sincerely asking because IDK.
@briankrebs Rufus can insert the updated carts into windows ISO’s. It’s possible that those certs could be compromised, but that’s the additional downloads you’re seeing from what I saw in the video from
@briankrebs ...installation? its a portable app. do you still have the actual download link?
I just downloaded it last week (from rufus[.]ie) to a Linux machine to run with Wine and had no issues with ClamAV or the Linux machine.
@briankrebs Has your CoPilot gone rogue?
@ModernMaslow I don't use AI. At least on purpose.
@briankrebs Somehow I don't think the Tech Bros will consult you first.
@briankrebs Do you happen to have the hash of the file you received? I just pulled https://github.com/pbatard/rufus/releases/download/v4.15/rufus-4.15.exe (which is also the link that is on rufus.ie) and it gave me 84c8a437f8af89257524478489e5c85f1edf25f761d299e2bcde46ac0afbe106 rufus-4.15.exe which is clean according to virustotal.
@cubeos As I mentioned, the installer put up several prompts to install other components, so those probably wouldn't come up on a scan of the installer itself.
@briankrebs I'm just surprised that the behavior analysis of VT didn't catch these either. https://www.virustotal.com/gui/file/84c8a437f8af89257524478489e5c85f1edf25f761d299e2bcde46ac0afbe106/behavior says it's been reanalyzed 2h ago.
@cubeos you'd have to put it through something like any.run to view the actual stuff that gets installed when you run it. they expired my subscription or I would do it myself.
@briankrebs So I hate to be snarky, but "dd" has been there all along people. Having to install an entire 3rd party application, for something that the OS should have stable, reliable methods for, to format a storage device and transfer a standard filesystem image to it, is intolerable. But it's Windows...depends on curl to download its own updates...
@jab01701mid @briankrebs ironically the official windows installer builder does support writing to USB directly but it doesn't have the customisation that Rufus offers for slipstreaming and deshittifying. But for other non-Windows ISOs? Yeah.
Though it should be noted that for awhile now a lot of images are designed such that if you mount them and copy their contents to the USB partition bare it'll work just fine and this can be done from stock Windows
@jab01701mid You're absolutely right. It's like the flashlight app. Duh. Should be included so people don't search for it and install malware.
@briankrebs huh, that is the traditional official domain for it, isn't it?
looks disputed as a windows defender false positive.
@m3t00 again, the behavior will likely not be noticed by scanning the installer file. Needs a sandbox installation to find out what's really going on.
@briankrebs
What chance do I have, if you get hit?
However, in my defense Google's default search results list rufus[.]ie as the authoritative site
@briankrebs WHO ORDERED THE LARGE DEEPDISH SANDBOX ANALYSIS??
https://app.any.run/tasks/90d1d270-a93f-498f-81d7-84d5e8f156bf
@jordinki thank god! the Internet gods DO exist!
@briankrebs @jordinki it's Gods all the way down.
@briankrebs the link the to official site from the GitHub page also links to Rufus.ie so something ain’t right
@briankrebs I used the Portable one when I ran Windows. Is it just the installer, or is the portable one infected, too?
Install Fedizen
Get the full app experience
@briankrebs Yeah wait, forget what I wrote in this post before. Realtime protection being disabled seems to be standard behaviour at least for for the W10 version of Windows Sandbox? There's just no AV providers installed...
Somehow never noticed when using that thing before 🤦♂️
Sorry for the noise.