The developers of open source video transcoder app Handbrake have issued a security warning to Mac users after a mirror download server hosting the software was hacked.
The alert was issued on Saturday after it was discovered that the original HandBrake-1.0.7.dmg installer file on mirror server download.handbrake.fr had been replaced by a malicious file.
The affected server has been shut down for investigation, but developers are warning that users who downloaded the software from the server between 14:30 UTC May 2 and 11:00 UTC May 6 have a 50/50 chance of their system being infected by a trojan. "If you see a process called 'Activity_agent' in the OS X Activity Monitor application, you are infected," read the alert.
To remove the malware from an infected computer, users need to open up the Terminal application and run the following commands:
- launchctl unload ~/Library/LaunchAgents/fr.handbrake.activity_agent.plist
- rm -rf ~/Library/RenderFiles/activity_agent.app
- if ~/Library/VideoFrameworks/ contains proton.zip, remove the folder
Users should then remove any installs of the Handbrake.app they have on their system. As an extra security recommendation, users should also change all the passwords that may reside in their OSX KeyChain or in any browser password stores.
The malware in question is a new variant of OSX.PROTON, a Mac-based remote access trojan that gives the attacker root-access privileges. Apple updated its macOS security software XProtect in February to defend against the original Proton malware. Apple initiated the process to update its XProtect definitions on Saturday and the update should already be rolling out to machines silently and automatically.
Handbrake users should note that the primary download mirror and the Handbrake website were unaffected by the hack. Downloads via the application's built-in updater with 1.0 and later are also unaffected, since these are verified by a DSA Signature and won't install if they don't pass. However, users with Handbrake 0.10.5 and earlier who used the application's built-in updater should check their system, as these versions don't have the verification feature.
For reference, HandBrake.dmg files with the following checksums are infected:
SHA1: 0935a43ca90c6c419a49e4f8f1d75e68cd70b274 / SHA256: 013623e5e50449bbdf6943549d8224a122aa6c42bd3300a1bd2b743b01ae6793
(Thanks, Alfonso!)
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Top Rated Comments
It amazes me how people quickly complain and comment negatively on an open source "free" software that they don't have to pay anything for. Give them a break. This is not apple with unlimited resources and employees with high paying salaries who are expected to have everything protected and secure and perfect. They don't get paid. They were quick to reveal the issue and not hide anything.
Complainers either don't write code, or if you do, you are doing it for money. They are not. Those who use their software appreciate their hard work and appreciate their honesty to reveal the issue quickly and not hide anything so we can fix the issue on our side. This stuff happens occasionally. If you paid for the software, then "yeah"..complain. They have limited resources, so give them a break as they work hard to resolve the issue. I am sure someone had no sleep trying to quickly fix the problem and then have to go to their day job after, just to fix a free program that they offer to the world to use.
Appreciate the open source community that gives us a great program. Thanks for informing us right away so we can protect our systems and continue to use handbrake.
The developers themselves need to maintain hashes are correct.
I applaud them for telling it like it is, and finding solutions.
Pretty sure many apps are affected by such issues, but either they don't find out / don't say to their users.
That said, I'm posting because I nearly got caught by this. I download Handbrake last week and was surprised to see a dialog on launch asking me to enter my password to "install additional codecs". As a longtime Handbrake user I was certain that this was *not* normal, so I declined. Shortly afterword I was shown another dialog, independent from Handbrake, purporting to be from the system "Network Configuration" which needed my password to "update DHCP settings". As this was also something I was unfamiliar with, I again declined but the dialog immediately reappeared upon clicking cancel and I had to restart the computer to make it go away. So yeah, if you see any suspicious password dialogs, do NOT enter your password.