Windows DRM-Protected Files Used To Decloak Tor Browser Users (bleepingcomputer.com) 150
An anonymous reader writes from a report via BleepingComputer: Downloading and trying to open Windows DRM-protected multimedia files can deanonymize Tor Browser users and reveal their real IP addresses, security researchers from Hacker House have warned. On Windows, multimedia files encoded with special Microsoft SDK will automatically open an IE window and access a URL to check the file's license. Since this request is sent outside of the Tor Browser and without user interaction, this can be used to ping law enforcement servers and detect the user's real IP address and other details. For example, law enforcement could host properly signed DRM-protected files on sites pretending to host child pornography. When a user would try to view the file, the DRM multimedia file would use Internet Explorer to ping a server belonging to the law enforcement agency. The same tactic can also be used to target ISIS militants trying to view propaganda videos, illegal drug and weapons buyers trying to view video product demos, political dissidents viewing news videos, and more. A video of the attack is available here.
Umm... just WMVs? (Score:4, Interesting)
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Better still is Whonix (VM isolation for both Tor and Torbrowser). TAILS may have a fancy configuration to attempt leak prevention, but privilege escalation attacks are a dime a dozen on Linux.
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Whonix runs in a VM on top of a host OS. VM escape flaws are a thing, and if malicious code gets out of the VM then it's running on your host OS. I guess you could have a dedicated host OS with nothing on it. Anyway, running code in a VM is not without risk.
Booting Tails directly on the machine has a few advantages. Nothing saved to disk, no evidence you even ran it.
Neither system is perfect and both have their advantages.
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Neither system is perfect and both have their advantages.
and *both* are vastly better than plain Tor on otherwise vanilla Windows host.
-nB
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Running code isolated by a bare-metal VMM like Xen is much better than running it in bare-metal Linux from a security standpoint. Comparing Linux and Xen vulns, there is a stark contrast. And that is even before one subtracts DOS and vulns in superfluous Qemu components.
So, yes, VM breakout "is a thing", but mainly on hypervisors that were designed to run on top of a complex OS and dedicated foremost to administrative convenience.
Tails has the drawback that its vulnerable to DMA attacks, i.e. if your NIC or
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tails in a vm would have prevented this.
tails is about disallowing non-tor connections for the primary user.
Re: Umm... just WMVs? (Score:4, Insightful)
Does it also prevent a user process from knowing the real IP address? (I genuinely don't know.) If it didn't, then I suppose the phone-home mechanism would just query the IP and transmit it as data.
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Depends on your type of internet connection.
Usual DSL setup with some router at the dsl port and your pc at a lan interface of the router (or tails in a vm, talking to the host via a NAT-network (default on most vm softwares)), a malware running as the restricted user would only get the LAN ips and the tor-exit ip (not by reading it, but by using some kind of whatismyip service or directly accessing some honeypot/pleaselogme url).
Re:Umm... just WMVs? (Score:5, Informative)
The safest solution is to block outgoing traffic by default and whitelist what you want to allow in the firewall.
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Maybe an esoteric proxy configuration that only works with a manually configured browser could do?
But the easiest option is just to ditch windows if you're serious about security. And maybe also modern x86-based CPUs, since they usually contain ring -2 to -5 coprocessors with DMA, network access, and other niceties.
Re:Umm... just WMVs? (Score:5, Informative)
And of course, to do that, you would have to trust the windows firewall, which doesn't show everything.
If you run "Windows Firewall with Advanced Security" it shows absolutely everything. I have yet to find anything that bypasses the firewall. Even Windows 10's agressive updates don't work if you block by default, although I have no evidence of the telemetry one way or the other.
That said, if you have an application that runs with elevated security then it can add its own firewall rules. The way around that is to create a special user that just for editing the firewall entries, grant it access to the registry setting and revoke administrator rights. That's only required if you are paranoid though, or if you have a specific requirement. I did this to stop Steam from constantly creating firewall entries for itself and all games. I needed to lock it down to only work over my local connection to prevent it from downloading via my work when I set up a VPN to access the servers.
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And of course, to do that, you would have to trust the windows firewall, which doesn't show everything.
If you run "Windows Firewall with Advanced Security" it shows absolutely everything. I have yet to find anything that bypasses the firewall. Even Windows 10's agressive updates don't work if you block by default, although I have no evidence of the telemetry one way or the other.
That said, if you have an application that runs with elevated security then it can add its own firewall rules. The way around that is to create a special user that just for editing the firewall entries, grant it access to the registry setting and revoke administrator rights. That's only required if you are paranoid though, or if you have a specific requirement. I did this to stop Steam from constantly creating firewall entries for itself and all games. I needed to lock it down to only work over my local connection to prevent it from downloading via my work when I set up a VPN to access the servers.
In Linux its fairly trivial to set up the firewall to block all egress except via a VPN; you configure so that only the VPN can egress via the physical network adaptor (eg eth0) restricting port and destination IP address. Then allow traffic via the tun device used by OpenVPN. In this way you can't accidentally leak anything outside the VPN.
How do you do that in Windows? I never saw any ability to do firewalling by network adaptor.
Thanks
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How do you do that in Windows? I never saw any ability to do firewalling by network adaptor.
You can limit any firewall rule to work on one or more interface types on the Advanced tab of the rule's properties. This isn't quite as good as specifying the adaptor if you have really complicated networks, but it does the trick for 99.9% of cases. The three interface types are (as copied from the help file for the firewall):
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But how does the hardware firewall block specific applications from accessing the Internet?
By granting internet access on a per application basis with the software firewall, I don't have to worry about bugs or unintended consequences of some program have network access that I didn't expect. My media player only ever plays files from my computer, so I have never needed to grant it permission to talk to arbitrary servers, so this trick would never have affected me. It's a great way of neutering malware and ba
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What pocket-size hardware firewall do you recommend for use with a laptop computer?
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NextThingCo CHIP would be great for something like that. It's literally pocket sized, has built-in WiFi, and two interfaces at that - so one can connect to the external network, while the other one serves as an API, with the device serving as a bridge/firewall between the two. And it costs $10 (although you need to bring your own battery).
You'd have to set this all up yourself, though.
Re:Umm... just WMVs? (Score:5, Insightful)
The safest solution is to block outgoing traffic by default and whitelist what you want to allow in the firewall.
And avoid both DRM and Windows like the plague, even if you're not doing something that would get you in trouble with your government.
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Or use a TOR hardware device to make sure ALL traffic headed out your NIC is anonymized...
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Speaking of firewalls, does anyone know of an application-level egress firewall, like Little Snitch [obdev.at], for Windows or Linux?
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"Or with countless pieces of software out there?"
Exactly! That's why one should use a VPN on top of TOR. (or under in this case:-)
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"Or with countless pieces of software out there?"
Exactly! That's why one should use a VPN on top of TOR. (or under in this case:-)
VPN into Tor then VPN through Tor. Then use 7 proxies.
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The issue here is that the DRM process pings a custom server. Most modern software doesn't randomly let the content creator reach the public internet. E.g doing this in acrobat would result in a confirmation being presented to the user that content is about to be retrieved from the internet.
Most of this software also needs to be installed, whereas Windows just exists on many target devices already.
Any DRM that phones home will do that (Score:3)
Of course that means the FBI has be able to host the files on the server, and has to have sufficient control to deliver a uniquely keyed file to the users they wish to target. Sort of implies you have hit a honeypot if they get you with that.
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I don't know that I am comfortable with that. Should everyone who bought a copy of the Anarchist's cookbook expect a higher level of surveillance ?
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I don't know that I am comfortable with that. Should everyone who bought a copy of the Anarchist's cookbook expect a higher level of surveillance ?
I don't think so...
But if you downloaded it illegally?
Well, it might be bad policy to short an Anarchist's royalty check...
Oh, don't mess with the Alchemists either...
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Re: Anarchist's cookbook (Score:1)
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Quick Workaround (Score:5, Interesting)
1. Determine which TOR-nodes you're talking to. (Netstat or Ethereal) /32s the TOR-nodes are on through the ISP router
2. Remove default route through your ISPs router
3. Add specific routes to the
Traffic routed through TOR will work fine.
Traffic going outside of TOR will fail except for the local network (your home or office LAN).
E
Quicker workaround (Score:2)
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stop using IE (physically break it) .asf .wma .wmv files. seriously these formats should be erased from existence!!!
stop using windows
stop using
deny all media players access to the web. seriously no video or music HAS to have access to the internet unless it has drm shit. and you should NEVEr buy drmed music or videos. if you want lyrics, open your browser.
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If all else fails you could try obeying the law.
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From the summary:
"target ISIS militants trying to view propaganda videos, illegal drug and weapons buyers trying to view video product demos, political dissidents viewing news videos"
Last I checked, merely viewing propaganda videos, product demos, or news videos is not illegal. At least not yet.
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well at least they can't be sent to jail then.
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> stop using IE (physically break it)
I am not sure, you know what physically means.
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install Linux. Heck, in a VM if you're lazy.
In a VM if you're smart.... https://www.qubes-os.org/ [qubes-os.org]
Re: Qubes-OS (Score:1)
Re: VM (Score:1)
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So watch netflix on your Android TV, whilst doing other stuff on your computer. I do this all of the time, well, not netflix, but streamed youtube et al, whilst gaming, shopping etc. and no, I do not want corporations spying on me, I do not want them to install software without my specific permission, nor do I want them to delete content without my permission. You can see it coming, the only copy of a wedding video, fresh from the camera, stored on windows and because ohh ahh copyrighted music for which the
Re:Quick Workaround (Score:4, Funny)
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the only copy of a wedding video, fresh from the camera, stored on windows and because ohh ahh copyrighted music for which the owner does not permission is in the background
Next time try planning ahead and encouraging a policy to play only free [freedomdefined.org] music at weddings in your extended family.
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Any file could have a link that gets used on any modern OS trying to help with a search by showing a preview of that file "live" during desktop search results.
You've convinced me! (Score:1)
I'm reinstalling DOS right now.
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Or just stop using Windows.
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Problem is Tor likes to switch nodes at least every 15 minutes.
A better option is to route everything through a router running Tor. Nothing can avoid going through it, no matter how compromised your machine becomes nothing can bypass it to get your real IP address.
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useful workaround:
iptables -A OUTPUT -m user --uid vpnuser -d 127.0.0.1 --dport 9050 -j ACCEPT
iptables -A OUTPUT -m user --uid vpnuser -j REJECT
and tor running as another user.
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<?xml version="1.0" encoding="utf-8"?>
<direct>
<chain table="filter" chain="NONET_DENY" ipv="ipv4"/>
<rule table="filter" chain="NONET_DENY" ipv="ipv4" priority="0">--match owner '!' --gid-owner nonet --jump RETURN</rule>
<rule table="filter" chain="NONET_DENY" ipv="ipv4" priority="1">--destination 127.0.0.1 --jump RETURN</rule>
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For a really sophisticated solution, have a look into "ip rule", the "fwmark" option of iptables and matching cgroups.
The advantage: What is in a cgroup stays in a cgroup. Even when a program changes user, its process and children are still in the cgroup.
Of course, who is able to control the cgroup(s) can reassign the processes. So you may consider root putting the process in a cgroup, which it cannot escape without root privileges.
Re:I'm ok with this behavior in those use cases (Score:4, Informative)
Well if you're up to no good you certainly should learn linux and also get some good info on computer security. Use one computer for fun, youtube, surfing, contacting family and friends, playing games. For anything where security is paramount you should use a hardened system. The more dire the ramifications of a breach the more hardened. Perhaps a CD based OS that is impossible to overwrite the system files. A custom built router with a good open source router OS. Keep all files encrypted on a removable micro-SD card. I'm sure if I was involved in anything like this I'd think of other things to do and avoid. Mostly I'm astounded by how careless people engaged in seriously illegal activity often are.
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If you show up on an intelligence agency radar you are well and truly fucked. None of the national intelligence services have the resources to collect or process every bit being transmitted through the hellish labyrinth other wise known as the Internet. However, they do possess an array of tools and skills to use against specific targets. The whole mass data collection proposals were basically shit canned because the information flowing through the internet is 99% bullshit regurgitated by people with an IQ
Re:I'm ok with this behavior in those use cases (Score:5, Interesting)
"First they came for the kiddy fiddlers, and no one objected..." Then a month from now, the FBI is ordered to embed these bugs in videos of services at mosques, and videos of anti-Trump protests, and videos of CNN interviews, and seed them all around the internet to build The Bigly List of Brown People and Dissenters.
In the Bush era, I would have laughed this off as a slippery slope argument. In present times, knowing what Snowden has taught us and watching the current political climate, I don't see it as a laughing matter.
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This summary sounds oddly specific.
Re:Not Tor Problems! (Score:4, Interesting)
They aren't using it to watch entertainment videos. They are going to underground web sites (child porn, drugs, weapons etc) and being tricked into viewing a video put there by law enforcement that is designed to phone home in this way.
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I have to wonder at the ethics of law enforcement hosting illegal content.
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I don't think its illegal to download a file with a kitten. So they may log the ips, but what do they want to sue the user for?
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She wasn't actually turning them in, she was fucking with their minds. You might need to get your own stupid ass in the kitchen, bitch.
Not so fast... Re:Not Tor Problems! (Score:4, Informative)
Vice has an article titled "Countries that Use Tor Most Are Either Highly Repressive or Highly Liberal [vice.com]," that you might want to read.
If that were the only reason to use Tor you would be absolutely right. But my understanding is that Tor is also used (used more in fact) in countries where the governments will throw you in jail or kill you for the only reason of trying to exercise free speech. Those governments can employ the same tactics to find and jail political dissenters. And that would be a shame. It would be nice to be able to figure out the wheat from the chaff. But there are many governments that I wouldn't want making that determination, including the one being lead by the latest POTUS. In fact Tor might become a necessity for free speech in the USA soon.
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For all I know they are just people who are using it to watch entertainment videos.
Or to just browse the web without facebook, google, nsa, etc. recording your every move.
In other words: exercising your right to privacy.
...they called my job and asked if they could speak to me concerning a child porn.
Seriously? Already at the start of their investigation they are damaging your career by mentioning to your colleagues they want to talk to you about child porn?
That's a very malicious lack of discretion.
It's always the pedos (Score:3, Insightful)
So tired of these stories making reference to pedos. Sure they exist, but every time the govt is caught spying, the media trots out the pedophiles to justify it. Not everyone who views "questionable" content is a crook. I've read plenty of articles, and watched plenty of videos, on how to make bombs and explosives, yet have never actually made one. Nor do I ever plan to do so. Forbidden knowledge and all that.....
It's right there in the FAQ:Don't torrent over Tor (Score:3, Informative)
"Don't torrent over Tor
Torrent file-sharing applications have been observed to ignore proxy settings and make direct connections even when they are told to use Tor. Even if your torrent application connects only through Tor, you will often send out your real IP address in the tracker GET request, because that's how torrents work. Not only do you deanonymize your torrent traffic and your other simultaneous Tor web traffic this way, you also slow down the entire Tor network for everyone else."
https://www.torproject.org/download/download.html.en#warning [slashdot.org]
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WMP Settings (Score:3)
The Windows media player - at least through Windows 7 - had an option to "download usage rights automatically when I play or sync a file". I wonder if this "attack" still takes place if this feature is not enabled.
Re:WMP Settings (Score:4, Interesting)
I was thinking the same thing. I always uncheck all those boxes when I launch WMP for the first time.
Though really, I don't think I have launched WMP in years... why bother when you have VLC?
VLC is associated with all of the file media file types that Windows knows about so is the DRM laden WMV (or whatever) able to call WMP explicitly when you launch it? I don't think that is how it works. Even if it did, if you have never run WMP before, you will get the first run dialog which has the option you mention plain as day as a checkbox.
Seems like this tracking mechanism is to catch total morons.
Missed something important (Score:4, Insightful)
For example, law enforcement could host properly signed DRM-protected files on sites pretending to host child pornography.
Apparently it's no longer even worth noting that representatives of the US government will run a child porn site offering downloads!
Again.
Yes, "pretending". So a honeypot without honey. That'll get real far now won't it?
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They're only skimming the most ignorant off the top of the cesspool.
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If my only choice is to side with pedos or a tyrannical government, I side with the pedos. Out of pure self interest.
I'm way over 18. Guess which of the two is a threat to me.
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I'd like to see a slashdot article on honeytraps. No, I'm not an expert at identifying and avoiding them.
Ask OS makers next? (Score:4, Insightful)
Give the checksums to all the big US OS brands to add to their new OS AV efforts.
Recored every IP that responds to a checksum as part of anti virus spread tracking if the user "allowed" such self reporting to the OS.
Use the advanced and near instant indexing on most modern OS to report the file when it is opened and have the users OS report that file on the OS brand?
Remove and replace the checksum list for next week so it will not slow any modern computer down.
Any advance user could test the file in any way and find no issue.
A new OS AV update of a few megabytes spread over a few days per week could hold how many new file checksums per week every week?
The OS would do all the reporting on an average user who trusted the OS brand with AV.
Re:Ask OS makers next? (Score:4, Interesting)
Next? There's a high likelihood this is already happening in Windows 10. Every time you open a file, Windows 10 is sending unknown "telemetry" back to the mother ship. Those Windows Defender and Microsoft Security Essentials updates you get every day? They're hash lists. You can bet your ass those lists contain more than just virus signatures, and matches are being recorded somewhere.
Opsec (Score:4, Insightful)
If you require perfect opsec all the time, you are doomed eventually.
Also, who the hell does this? The only sane way to use TOR for something dangerous is on a machine that has never and will never be connected to the internet directly or through NAT. And that computer's only network jack should be plugged into a disposable router running a bootable live system that does all-TOR all-day.
In other words, even if the client computer is trying to turn you in, which it is, it shouldn't know anything other than the reserved/private IP that your router gives it and the IP or onion address your browser is visiting.
A good point (Score:1)
Hosting Illegal Child Pornography is ILLEGAL (Score:4)
Law enforcement should be not allowed to host child porn, even if it is trapped. It is clearly entrapment. IMO this is clearly a serious breach of the laws. If the material is illegal, then law enforcement should not be allowed to present it to the public. It presents a danger to the casual web surfer that is artificially implanted. The material is illegal. Period. No honeypots should be allowed.
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Might be illegal, but look up entrapment (Score:2)
Distributing child porn, when done by the FBI, may be illegal. I don't feel like reading the statute right now, many laws have exceptions for law enforcement in the course of their duties.
That, however, has nothing whatsoever to do with entrapment. Entrapment is when a person with no intention of committing any crime is induced to do so by the police.
If a person decides of their own free will to go to a child porn site and start downloading videos called "12 year old fucked.wmv" there is no entrapment. The
Entrapment = coerced into committing a crime (Score:1)
It's not entrapment, because they're not inducing people to do something they wouldn't already do. Just like if they have a fake prostitute or drug-dealer who is actually a cop. If you walk up and ask for services, you're busted. If they don't approach you and start offering rather enthusiastically, it's not entrapment.
Now if they start sending people with banner ads "hey come to nasty site X", running sketchy redirects from legit adult sites, etc, then THAT is entrapment. People who went to the site willin
Use linux when you use Tor? (Score:2)
I find it funny how all the work arounds listed no one suggested the best work around. Use linux, don't use windows.
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Download an archive of many, many files. 10 files don't work out of many?
One phones home on OS X, Windows, Linux when clicked on or opened or searched for and a live preview is created with spotlight?
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using tor on windows, bad idea! (Score:2)
trusting your tor traffic to a closed source OS?
what could possibly go wrong...
an IP address is not reliable evidence. (Score:1)
It assumes an IP address can be traced to a particular user and only that user, this is not the case,
There could be openwireless.org nodes, Tor exit nodes, proxies, malware, badly secured/open access points or god knows what else.
The idea that an IP address is evidence of identity of the downloader has always been problematic at best.
Not news... (Score:2)
Malware makers have used DRM'd WMVs to launch IE to the exploit page of their choice for more than a decade, maybe two. The only media player I know dumb enough to load it by default is Microsoft's own, if you use VLC or really any other player you're safe.