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Microsoft Remotely Deleted Tor From Windows Machines To Stop Botnet
An anonymous reader writes "Microsoft remotely deleted old versions of Tor anonymizing software from Windows machines to prevent them from being exploited by Sefnit, a botnet that spread through the Tor network. It's unclear how many machines were affected, but the total number of computers on the Tor network ballooned from 1 million to 5.5 million as Sefnit spread. 'By October, the Tor network had dropped two million users thanks to Sefnit clients that had been axed. No one, not even the Tor developers themselves, knew how Microsoft had gone on a silent offensive against such a big opponent and won a decisive battle,' the Daily Dot reported. In a blog post, Microsoft claimed it views Tor as a 'good application,' but leaving it installed presented a severe threat to the infected machines."
No one, not even the Tor developers themselves, knew how Microsoft had gone on a silent offensive against such a big opponent and won a decisive battle
It seems pretty obvious - the people who's machine had Tor removed didn't know it was installed and weren't using it to begin with. When MS removed it, they didn't notice or complain.
So called Anti-virus software is a kill switch. So everyone who knew their Windows PC was running Windows Security Essentials or any of the other Microsoft AV products knew.
Yeah ... when every few weeks or so Windows Update tells me it's going to download something called the Malicious Software Removal Tool, I've always wondered what it did. We might have a few new clues here.
Breakfast served all day!
Who knew?
"Malicious Software Removal Tool" has been a Windows update for years. (Since 2005 http://en.wikipedia.org/wiki/Windows_Malicious_Software_Removal_Tool) What did you think it did? You have the option of not running it. If the update is selected / run it is a local program run one time after updates are installed that "checks your computer for infection by specific, prevalent malicious software (including Blaster, Sasser, and Mydoom) and helps to remove the infection if it is found. Microsoft will release an updated version of this tool on the second Tuesday of each month."
http://www.microsoft.com/en-ca/download/malicious-software-removal-tool-details.aspx
This doesn't sound much different to any other anti-virus removal. Microsoft almost certainly used the Microsoft Security Essential update to kill Sefnit, as they do with so many other viruses.
"the total number of computers on the Tor network ballooned from 1 million to 5.5 million as Sefnit spread"
These weren't dedicated Tor nodes that were taken offline because they were being used for malicious purposes, these were infected PCs with a virus that used Tor as the communication protocol. An outdated and vulnerable version of Tor was hidden in a "location that almost no human user would"
If a PC was infected with Sefnit and had the signature old version of Tor in the hidden location, Tor was removed because it's logically the case that Tor was just part of the virus payload. Because of the unique install directory, there wasn't even a remote chance for false positives. Publicly available tools that can be used for good or bad are hijacked by viruses all the time, and it's never a surprise if an anti-virus removes that tool when the virus specific files are removed.
Well we do know if we bother to RTFA.
This is no different from anti-virus, because it WAS the Microsoft anti-virus tool that did it. A specific version of TOR in a specific hidden directory being part of the virus payload.
Talk of not owning your own computer is nonsense. You are free to not run AV software if you prefer. It would be a dumb move, but you are free to do it.
Some people find TOR using a Chrome browser. Should they have the authority to remove that too only to tell you about it later in a blog?
No, of course not. Old, known-bad versions of TOR that have numerous exploits active in the wild are removed. Not Chrome browser as it's not malicious software.
To quote another poster a few threads down
If a PC was infected with Sefnit and had the signature old version of Tor in the hidden location, Tor was removed because it's logically the case that Tor was just part of the virus payload. Because of the unique install directory, there wasn't even a remote chance for false positives. Publicly available tools that can be used for good or bad are hijacked by viruses all the time, and it's never a surprise if an anti-virus removes that tool when the virus specific files are removed.
Specialist Mac support for creative pros, Melbourne
I'm sorry, but your thoughtful and well-written response is counter to the "Me hate Microsoft me LOVE TOR" groupthink on Slashdot, where facts are irrelevant and just muddy the waters.
Please move along.
(You're welcome to join me as I sit quietly in the corner, waiting to get modded down to troll.)
Did some more digging. Here are the details (from http://blogs.technet.com/b/mmpc/archive/2014/01/09/tackling-the-sefnit-botnet-tor-hazard.aspx) :
Cleanup efforts
Since the Sefnit-caused Tor eruption in August, we have worked to curb this risk. In this process, we consulted with Tor project developers to help plan the cleanup. We retroactively remediated machines that had previously been cleaned of Sefnit but still had a Sefnit-added Tor service:
October 27, 2013: We modified our signatures to remove the Sefnit-added Tor client service. Signature and remediation are included in all Microsoft security software, including Microsoft Security Essentials, Windows Defender on Windows 8, Microsoft Safety Scanner, Microsoft System Center Endpoint Protection, and Windows Defender Offline.
November 12, 2013: Signature and remediation is included in Malicious Software Removal Tool and delivered through Windows Update/Microsoft Update.
This sig has been enciphered with a one-time pad. It could say almost anything.
Some people find TOR using a Chrome browser. Should they have the authority to remove that too only to tell you about it later in a blog?
RTFA:
"To fight back, Microsoft remotely removed the program from as many computers as it could, along with the Tor clients it used."
Sounds like they removed the malware and the files it downloaded.
Microsoft Security Essentials is antivirus software. By definition it must have the authority to remove, isolate, disable, and delete software from your computer. The computer owners installed MS Security Essentials precisely to perform this specific service.
Have any Tor installations been removed that were not associated with Sefnit? It appears to me that the only software that was removed was the specific version of Tor that Sefnit used and, in most cases, when the Tor client has been installed a system service (which is very, very non-standard). MS did not remove the most recent version of the client.
You're just spreading FUD about a non-story. This is less interesting than all those stories about antivirus false positives rendering Windows unable to boot.
The road to tyranny has always been paved with claims of necessity.
He surmises that Microsoft used its Microsoft Security Essentials software to eliminate the programs, a program users must install themselves.
Or he could read Microsoft's own statement, where they say exactly how they eliminated Tor:
October 27, 2013: We modified our signatures to remove the Sefnit-added Tor client service. Signature and remediation are included in all Microsoft security software, including Microsoft Security Essentials, Windows Defender on Windows 8, Microsoft Safety Scanner, Microsoft System Center Endpoint Protection, and Windows Defender Offline.
November 12, 2013: Signature and remediation is included in Malicious Software Removal Tool and delivered through Windows Update/Microsoft Update.
If you RTFA, you will find that the Microsoft guys first figured out that Sefnit installs Tor in a very specific, unusual way in very specific, unusual location, then contacted the Tor developers to ask if there is any chance a legitimate user would do the same thing. Only then, they proceeded to remove Tor versions that were installed in this very specific way and location. Without any doubt, one of their operating parameters was to avoid collateral damage at all cost; if they screwed up, they could have caused the Microsoft PR disaster of the decade (and boy, is there stiff competition for that title).