Live data from Hacker News

Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

transmissionbt.com

61–70 of 146 posts

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#61
post #19
post #5

Second time that this has happened to Transmission this year. Last time a ransomware got included. If you're a Transmission user then be very cautious when installing new versions.

You were only at risk when downloaded fresh copies from the website. Updates were checked by the already installed Transmission.

Except that time where the auto update mechanism was actually distributing a hacked version

http://www.macrumors.com/2016/03/07/transmission-malware-dow...

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#62
post #19

Earlier quoted context omitted.

You were only at risk when downloaded fresh copies from the website. Updates were checked by the already installed Transmission.

Except that time where the auto update mechanism was actually distributing a hacked version http://www.macrumors.com/2016/03/07/transmission-malware-dow...

No it did not. They distributed a new version via the build-in updater to try to remove the malware from the copies downloaded from the website. Sparkle use a digital signature and the malware author did not have the private key to create a valid signature for the update. So even if a malware was downloaded, Transmission would report a "invalid archive downloaded" error.

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#63

So what happened with the codesigning? That's pretty much the only viable line of defense for the average user (nobody is going to be verifying SHA signatures, or the site is going to be compromised along with the download) Was the malware version also signed with an official Apple Developer ID? The same ID? Is a change of ID verified with the auto-updater? If there was a malicious Developer ID, has it been revoked b…

According to this article [1], the compromised app was indeed signed – but with a different Developer ID than usual.

Anyone with a credit card can sign up for Apple's developer program and start signing apps.

[1] http://www.welivesecurity.com/2016/08/30/osxkeydnap-spreads-...

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#64
post #27

Earlier quoted context omitted.

Main reason that I only install stuff like this from my distro's repositories. Anyone know if this would have affected homebrew and such on OSX?

Homebrew packages verify checksums, so very unlikely to be affected.

Probably a good idea to turn off auto-update from Transmission's preferences and only use

    brew update && brew cask install --force transmission
to update. Even though they're also meant to be checksummed, I can't know whether an attacker also compromised the checksum mechanism.

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#65
post #60
post #41

Earlier quoted context omitted.

And to run it from the clipboard: pbpaste | sh -

If anyone wonders why this is taking too long, you may have done the same daft thing I just did, which was to copy the first command and then copy pbpaste | sh - . The latter will of course create an infinite loop.

Why would copying two strings to the clipboard lead to an infinite loop?

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#66
post #24

Are Transmission releases usually codesigned?

Yes. And updates are checked within the Transmission app.

Looks like it was signed by a different developer:

https://news.ycombinator.com/item?id=12403906

In comparison to Windows, macOS doesn't really seem to show the developer in the normal user flow.

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#67
post #47

Earlier quoted context omitted.

Yes, totally, if you want to make the best decision, then you have to keep up with the news. That's why I'm interested in other opinions about this, because there's a lot of datapoints you need to factor into a decision. It's not a simple decision. That's work, and we are lazy humans, you're right. But, I don't wait a whole week if the update is from an organization which I think I can trust not to totally botch an u…

It's more like a botched update from Microsoft, Apple, etc. will be noticed by lots of people within one or two days.

The size of the user base is certainly an important factor. To maybe exaggerate a contrary opinion though, I'd say that users of, for example, Ubuntu Linux, are far more alert to security issues than Microsoft customers.

I'm not totally disagreeing, I'm just trying to say that calculating a confidence score for software updates is not simple. Maybe it's clearer if I give you a real-world example: I use cryptocurrencies to move moderately large amounts of capital in my business, and so my paranoia-level for software installed on the single, air-gapped laptop that handles cryptocurrencies is sky high and crazy cautious. My other business is separated from that, and I can be much more relaxed about software updates for it, because the risks are much lower.

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#68
post #65
post #60

Earlier quoted context omitted.

If anyone wonders why this is taking too long, you may have done the same daft thing I just did, which was to copy the first command and then copy pbpaste | sh - . The latter will of course create an infinite loop.

Why would copying two strings to the clipboard lead to an infinite loop?

[deleted]

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#69
post #65
post #60

Earlier quoted context omitted.

If anyone wonders why this is taking too long, you may have done the same daft thing I just did, which was to copy the first command and then copy pbpaste | sh - . The latter will of course create an infinite loop.

Why would copying two strings to the clipboard lead to an infinite loop?

If you have `pbpaste | sh -` on your clipboard and then paste it into a terminal, it'll continually execute itself.

(`pbpaste | sh - | pbpaste | sh - | pbpaste | sh - | ... | pbpaste | sh -`)

Re: Transmission BitTorrent Client OSX/Keydnap Malware Incident Q+A

#70
post #65
post #60

Earlier quoted context omitted.

If anyone wonders why this is taking too long, you may have done the same daft thing I just did, which was to copy the first command and then copy pbpaste | sh - . The latter will of course create an infinite loop.

Why would copying two strings to the clipboard lead to an infinite loop?

I believe it would the same as this I think?

  pbpaste | sh - | sh - ...
Post reply on HN