Washington Post Says Use Linux To Avoid Bank Fraud

christian.einfeldt writes "Washington Post Security Fix columnist Brian Krebs recommends that banking customers consider using a Linux LiveCD, rather than Microsoft Windows, to access their on-line banking. He tells a story of two businesses that lost $100K and $447K, respectively, when thieves — armed with malware on the company controller's PC — were able to intercept one of the controller's log-in codes, and then delay the controller from logging in. Krebs notes that he is not alone in recommending the use of non-Windows machines for banking; The Financial Services Information Sharing and Analysis Center, an industry group supported by some of the world's largest banks, recently issued guidelines urging businesses to carry out all online banking activities from 'a stand-alone, hardened, and completely locked down computer system from where regular e-mail and Web browsing [are] not possible.' Krebs concludes his article with a link to an earlier column in which he steps readers through the process of booting a Linux LiveCD to do their on-line banking." Police in Australia offer similar advice, according to an item sent in by reader The Mad Hatterz: "Detective Inspector Bruce van der Graaf from the Computer Crime Investigation Unit told the hearing that he uses two rules to protect himself from cybercriminals when banking online. The first rule, he said, was to never click on hyperlinks to the banking site and the second was to avoid Microsoft Windows."

Comments

What about the banks?

[Profane MuthaFucka]

A little two factor authentication would be nice to see in American banks. Passwords just aren't adequate any more.

Re:What about the banks?

[nmb3000]

A little two factor authentication would be nice to see in American banks. Passwords just aren't adequate any more.

And how would an n-factor authentication scheme help when software on your computer is logging keystrokes, mouse gestures, and capturing images of your screen and then sending them near realtime to the bad guys?

If your computer has been compromised in this fashion, you've already lost. For you car enthusiasts, it's like adding additional locks to the car doors -- it doesn't help if the windows (haha) are already broken.

Re:What about the banks?

[FooAtWFU]

Security tokens are the second factor in two-factor authentication. The banks are just convinced that another-password is good enough, mostly because it's cheaper than doing it right.

Re:What about the banks?

[Cousarr]

You realize that the way two factor security is supposed to work is that is requires you to know something and have something right? The way that two factor security is usually done from what I've seen is requiring a password that the client knows and a rolling code from a small device the client has. As long as a bank does not allow that same rolling code to be used twice it doesn't matter what kind of keystroke logging, mouse gesture capturing, or screen recording is used nor how fast it is sent to the bad guys.

For you car enthusiasts, it's like taking the engine with you when you leave the car. Even if the car is hot-wired, it's not going anywhere without that thing you still have.

Re:What about the banks?

[some_guy_88]

The Commonwealth bank in Australia (and probably many others) sends you a random code via SMS to your phone that you have to type back in to the site in order to transfer money to an account you've never transfered to before.

Re:What about the banks?

[DarkFencer]

Though I agree two factor authentication is useful, the 'taking the engine' analogy overestimates the difficulty of breaking through it.

All the scammers have to do is instead of recording your keystrokes, gesturing, etc., they display a 'fake' copy of the bank to you through whatever software they have installed on your computer. They take the information you think you are sending to your bank (but are sending to them instead) and instantly have their scripts login to the site from their own systems (or some other bot on the net).

If they prevent your initial login to the site from happening, they can use your username + password + rolling code themselves if their software auto logs in.

This of course requires a user to go to a phishing site (miscellaneous.scammersite.com or something more complex), or requires the phisher to own the user's computer enough that they can intercept their connections & deal with the SSL certificate issues) while the phisher's automated software automatically goes to the real miscellaneousbank.com site.

Re:What about the banks?

[trawg]

And how would an n-factor authentication scheme help when software on your computer is logging keystrokes, mouse gestures, and capturing images of your screen and then sending them near realtime to the bad guys?

The way it works here with some banks in Australia is they send you a code via SMS when you try to issue a transfer from Internet banking. You need to enter the code into the website to continue the transaction. So the extra factor here of having the phone offers a pretty useful extra layer.

My bank doesn't offer it; I wish it did.

Re:What about the banks?

[jamstar7]

A little two factor authentication would be nice to see in American banks. Passwords just aren't adequate any more.

Per TFA, the banks in the two cases mentioned in the summary used two factor authentication. The hackers' malware delayed their access, and the hackers used a VPN tunnel to access the bank through the compromised computer.

Re:What about the banks?

[schon]

And asking me for my Mother's maiden name is really that much better? Or how about showing me an image that I picked out but will soon ignore after seeing that it never changes?

Those are both the same factor, just like a user's password.

Security factors are

1. something you know
2. something you have
3. something you are

In order to qualify as "two factor", you must have two of those (no, having two of the same factor doesn't count.)

So passwords, personal question, and favourite image are all examples of "something you know", and don't represent two-factor authentication.

The Security-token would be an example of "something you have", and thus combining them with a password would be two-factor authentication.

Re:What about the banks?

[mjwx]

And how would an n-factor authentication scheme help when software on your computer is logging keystrokes, mouse gestures, and capturing images of your screen and then sending them near realtime to the bad guys?

Because a 2 factor authentication token like an RSA key changes every 10 or so seconds so by the time Bad Guy #1 has finished parsing that log the 2nd authentication factor is out of date. The far cheaper way of doing this which most banks in Australia have started using is a one time password sent to you via SMS. This password works one time only (hence we call it a one time password, geddit) so if the Bad Guys(TM) get the entire password in real time and are reading their logs in real time then they still cant use it as the password has already been used.

Yes it's a band aid solution but at least it's a decent kind of band aid. The alternative is complaining that it doesn't work and then having nothing happen because no one has a better practicable idea.

Re:What about the banks?

[shird]

And do you realise this authentication scheme has also been broken?

The crooks these days are breaking into your account in real-time by using your security token code as you login, and preventing you from logging in.

Read the article, he mentions this.

Re:What about the banks?

[shird]

This can be automated easily enough.

Also, it's trivial to redirect the POST to login.cgi or add an entry to /etc/hosts for bank.com to a different site that just presents a 'failed to login' instead of logging in. Meanwhile your password, security code etc has been sent off to the bad guys machine which does an automated "transfer *.* funds to x" script using these credentials.

It's been done.

Re:What about the banks?

[Compholio]

Because a 2 factor authentication token like an RSA key changes every 10 or so seconds so by the time Bad Guy #1 has finished parsing that log the 2nd authentication factor is out of date. The far cheaper way of doing this which most banks in Australia have started using is a one time password sent to you via SMS. This password works one time only (hence we call it a one time password, geddit) so if the Bad Guys(TM) get the entire password in real time and are reading their logs in real time then they still cant use it as the password has already been used.

None of this will work with the problems described in the article, if someone has control of your computer then you're screwed no matter what kind of authentication you have. In one of the examples they specifically stated that crackers used the token code and delayed the customer's request:

Johnston's bank requires customers to enter the code from a Vasco security token. But the thieves - armed with malware on the company controller's PC - were able to intercept one of those codes when the controller tried to log in, and then delay the controller from logging in. Indeed, Johnston said the company's computer logs show that the controller logged into the system while the series of thefts was already in progress.

So, instead of the cracker getting blocked the customer would have been blocked because the "malware" made the customer's request come in AFTER the cracker's. If you were really clever you'd program the thing to intercept all the communication before it gets encrypted to go out to the bank and then fake the returned data so the user doesn't know that you're toying with them (yes, you can intercept the crypto library calls - I toyed with this some to get the Red Alert 3 Beta working on Wine). I don't know about you, but I can't think of a solid way around this interception (except having the bank only allow logins from a special custom browser that they load on a Live CD).

Re:What about the banks?

[Profane MuthaFucka]

That's not two factor, it's one factor. It's something you know, in two parts. A key fob introduces something you have.

A big problem with what you described is that 40 images to choose from is like adding one more character to your password, allowing lowercase, numbers, and 4 other punctuation marks only.

It doesn't add much to security at all, in other words.

Re:What about the banks?

[Eivind]

True, but it doens't have to be that expensive to do right. My bank offers two different solutions for the second-factor. One is s crypto-key tokenthing that they send you to hang on your keychain. (so you log in with a password + a 5-digit security token from the gadget)

The other is, quite simply your mobile phone. You enter your username and password, if correct, they send you a SMS with a 5-char one-time-password, you enter this and are in.

Yes, it adds 10 seconds to the login-procedure, but it's a very efficient way of stopping keyloggers and malware from learning how to access your account. Even if they successfully snoop your password, that doesn't help them aslong as they can't ALSO intercept SMS-traffic to your cellphone. This isn't IMPOSSIBLE offcourse, but it sure as hell raises the bar.

Re:What about the banks?

[jimicus]

Mitchell & Webb put this pretty well:

http://www.youtube.com/watch?v=CS9ptA3Ya9E

Re:What about the banks?

[Jason Levine]

As a victim of Identity Theft, I can tell you that banks and credit agencies just don't care. The bank writes off the loss due to fraud. The credit agency shrugs their shoulders at bad information in your credit file and tells *you* to fix it (while they happily go on reporting the bad information). In the case of stolen credit card numbers, the credit card company simply issues a new card and reverses the fraudulent charges. Meanwhile, the thief has their new television and the store is out a few thousand dollars.

In my case, the credit card company opened a line of credit for "me" even though the online application contained the wrong Mother's Maiden Name. I only found out about it because the thieves put in for a rush delivery of the card and *then* changed the address on the account. The card wound up at my house instead of their house/drop box/whatever. The incorrect maiden name and quick address change didn't set off any fraud alerts. Neither did "me" trying to get a $5,000 cash advance on the card prior to activating it. And when I called them about it, they refused to give me any information because "I might run out and kill the thief and then they're liable." They even gave the police department the runaround.

As I said, they just don't care. They'll do everything in their power to protect themselves. Even if protecting themselves in the short term means the identity thief gets away and commits more fraud against their business in the long term. In the end, you are only important to them insofar as how much green they can make off of you.

Re:VM?

[shird]

Because as the author explains in the comments, key loggers can run at the low level device driver level. At this level, it can hook key presses in a VM just as well as the host OS.

It's a pain, because nobody wants to go to the trouble of rebooting twice for the sake of paying a few bills. But it's the only way to be sure of a clean environment, unless your BIOS has been hacked. It's at least one good argument for the trusted platform, TPM, or whatever it is. In theory you could be sure that you are running only un-altered digitally signed executables and nothing else.

Re:Just Linux?

[sqrt(2)]

We're trying to SAVE money here

Alternate Headline

[Minwee]

"Washington Post Urges Thieves To Distribute Linux LiveCDs"

A few racks full of CDs in a highly visible place, or even cheap preloaded USB drives delivered right to the mark's front door along with a friendly letter explaining how running Linux would help improve security and thwart The Bad Guys could make your job of stealing from the clueless even easier than before.

Re:VM?

[fuzzyfuzzyfungus]

Presumably, if one is handling enough money that 100K or 450K could be stolen, one could afford a second computer and a 2 way KVM switch.

That doesn't solve the "but joe user doesn't want to reboot just to get to his overdrawn checking account" problem; but with real computers routinely showing up for $300 and lower, it isn't exactly an extremist position to suggest banking from dedicated hardware for any nontrivial amount of money.

Re:Just Linux?

[AvitarX]

I think the point is Boot CD, not Linux.

This would preclude any with an intelligent GUI (actually I am quite fond of Gnome at this point, but that wasn't what you meant).

If I am correct, using a Linux boot CD would make sense for Linux users too.

Re:terrible advice

[fuzzyfuzzyfungus]

Unless your browser is listening for incoming connections, or your bank is running third party banner ads(in which case, switch right the fuck yesterday), does a browser vulnerability really matter?

If you are using the LiveCD as a dedicated banking only environment, the only input your browser will see is your bank's website. If you can't trust user behavior, and want to really be sure, you could have it set to reject anything that doesn't have the bank's SSL cert. If your bank wants to 0wn you, you are already doomed. If no other site can reach your browser, your browser cannot be owned, no matter how buggy.

Re:terrible advice

[black3d]

Browser security is only an issue if you're visiting other sites, in the same session, on the same boot, on your LiveCD. Browsers on LiveCDs don't magically download malware from the internet by themselves - you have to direct them to. And most conventional malware must install itself - which won't happen on a LiveCD. There are a very few flash/js based attacks that work live in the same session - but really, if your either (a) your bank has third-party inline flash ads or (b) you don't trust java content from your bank's own website, then why are you banking with them online?

And going as far as questioning whether your CD burning software is infected is ridiculous. You can't be any more certain that your mouse doesn't have imbedded circuitry tracing your movement pattens, or your keyboard doesn't have a keylogger built directly into it, or the aliens aren't tapping directly into your cablings electromagnetic intereference patterns to directly access your bank account as you do. You're going to extremes purely for the point of argument, but although it may have passed you by, it was established several thousands years ago that "nothing is certain".

If you can imagine up scenarios like malware built into your cd-burning software specifically to target LiveCDs being used for online banking, I can't fathom how you trust a banks own employees enough to actually keep your money with them instead of under the mattress.

Devil's advocate: Deepfreeze?

[mlts]

Devil's advocate here:

Of course, a diskless system running Linux would reduce the chance of malware on clients, but perhaps if a company is dependent on Windows, almost as good security (and I state almost) would be obtained from denying admin access and using something like DeepFreeze, Windows SteadyState, or similar?

Combine DeepFreeze with AppLocker, some decent enterprise antivirus utilities, BitLocker, and the usual physical and BIOS protection on a machine, and one can make a decently locked down terminal that can cleanly run Windows apps. Should additional software be needed, no need to install it, just use something like VMWare ThinApp and have it runnable from a central location.

There is nothing wrong with a diskless system and booting from a CD-ROM. However, unless one creates a custom image with reliable enterprise level auditing tools, it becomes difficult to extract data from a group of PCs (and this is important for larger businesses come tax season, or regulatory compliance), and it is definitely an issue to add or update software without a reboot, unless it is a precompiled binary on a central server that people run.

Also, instead of running live CDs, why not consider going to a vendor like Wyse and going with truly thin technology? This way, there is little to no fiddling with the client side. If a thin terminal has a problem, just swap it out for another one, chuck the old one in the RMA box and be done with it. This is arguably a lot easier than the cost for maintaining standard PCs [1].

[1]: I'm primarily intending enterprise level here. For some SMBs, it is a lot cheaper to go with a boot CD and a generic PC, but for larger companies, it may mean more futzing around with stuff for their IT staff, especially on the scale of thousands of endpoints. If I had a startup with a call center of 5 people, PCs are a lot more economical. However, 500 to 1000 people in a non-technical call center, then I'd take a serious look at thin terminals and a beefy internal network fabric.

A smart bank would be ALL over this...

[davide marney]

A bank with any technical savvy would be immediately preparing a LiveCD/USB distro that boots as quickly as possible into a browser pre-configured with the bank's portal page set as the home page. The distro would contain nothing extraneous -- just enough for fast, safe banking. It would, of course, be thoroughly branded, but completely legit vis a vis source code and license notices. Give them away in the mail, or even sell USB drives.

Re:terrible advice

[Draek]

hey, who says your CD burning software isn't infected - implications on trusting trust and all.

I understand there's only a fine line between safety and paranoia, but the idea of a CD burning software having been compromised to detect Linux LiveCD ISOs and add a software keylogger to the system included therein is so far up in 'paranoia' territory it already got full citizenship and is considering running for president against "Elvis is hidden in Area 51" and "9/11 was planned by Israel to draw the US into the middle east".

Re:VM?

[Straker Skunk]

What about a Windows XP Live CD?

"Sir, there are some gentlemen here who say they are from an organization called the BSA. They want to see the license certificates for those Windows CDs we've been handing out..."

Re:Non-random bits on LiveCD can compromise securi

[slimjim8094]

Not Linux. Randomness comes from the time (hardware, persistent), but also from the randomness of network traffic and other driver miscellanea such as HDD head seek times, mouse movements, keystrokes, CPU temperature data, electrical noise on the power supply (with the right hardware)...

I can't say for sure, but I think Linux actually has the most secure random-number generator of any OS - excluding dedicated hardware. Enough that it can probably be fairly called true RNG instead for PRNG, as long as you use /dev/random instead of urandom.

I'll tell you what...

[bdwoolman]

What in the holy hell do people who make costumes have to do with any of this?

If you are going to rob a bank anonymously you absolutely need a costumer. The costumer is the person who dresses up the bank robber in his archetypal stripped shirt and handkerchief mask. Costumers are typically blond with big... ideas.