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Sneaky Blackmailing Virus That Encrypts Data
BaCa writes "Kaspersky Lab found a new variant of Gpcode which encrypts files with various extensions using an RSA encryption algorithm with a 1024-bit key. After Gpcode.ak encrypts files on the victim machine, it changes the extension of these files to ._CRYPT and places a text file named !_READ_ME_!.txt in the same folder. In the text file the criminal tells the victims that the file has been encrypted and offers to sell them a decryptor. Is this a look into the future where the majority of malware will function based on extortion?"
Question is, does the encryptor rewrite the data in-place, or just encrypt to a new file then delete the original? If the latter, the data is still recoverable with a simple undelete utility.
Seriously. In order for extortion to work, money has to change hands. Money can be traced, easily (don't believe what they say about Western Union). This is a great way to track down and capture the people who are spreading the virus. And the people whose files are encrypted could as easily have seen those files deleted, or worse. So it's no difference to them, except that they now have a hand in putting a crook behind bars.
The virus tossers are actually making their situation worse by turning to extortion. But they weren't all that bright to start with.
I don't know! Stop asking me those questions all the time. Is it obligatory to end every blurb with a question, or what?
Uh, if 1024-bit RSA was broken, the world of encryption security would collapse (at least for the short term). Could it happen? Sure, it's possible. Will it happen in time to save your pr0n collection? Highly unlikely.
For one thing, compromise of RSA encryption would render SSL useless.
The trust issue is that there is fundamentally no reason for the person receiving the money to follow through and send you the private keys to decrypt the data. If it was a known person, they'd be arrested, and since they're unknown there is no "reputational" factor that would make people more likely to pay based on the experience of others.
Just another moron criminal scheme from some douchebag who thinks he's found a get rich scheme. Just like other "genius" criminals, the fact is that the professionals in the field are smarter than the criminals.
This same thing happened in the late 80's (or maybe early 90's). Some hackers mailed a 5.25 inch floppy with some "free" software on it to thousands of people around the world. When you installed the software, it would hijack your PC and encrypt various files and you had to pay a ransom to get it back. There was a EULA and everything with the disk (which of course nobody read) which made it clear what would happen if you installed the disk. Perhaps someone can remember what it was called.
Joe User: Someone set us up the encryption. We get no data. Readme file turn on.
Jack Hacker: How are you gentlemen? All your data are belong to us.
I'm not going to worry about this.
I'm sure the fine folks of our Government are watching everything that happens on my computer & will promptly decrypt my files for me using their built-in back doors.
Wanna fight ? Bend over, stick your head up your ass, and fight for air.
My computer was infected by this virus... luckily all my files were already encrypted so all it did was make plain-text versions of everything and leave me a file asking for a donation
This will probably be seen as flamebait, but using Linux makes you no more or less susceptible to data loss. Only the time and expense of recovery differs.
And not as much as it would seem.
ps - this is why I have three copies of everything important to me and my wife, in two different locations, rarely more than 2 days out. She doesn't question me about this for a few weeks after she askes "Honey, I can't find........". She still doesn't understand about 12 years of email archives... Go figure.
deleting the extra space after periods so i can stay relevant, yeah.
"We have encrypted your illegally copied music files. Put $5000 in unmarked bills in a plain brown paper sack and mail it to: RIAA Washington, D.C. no later than midnight tonight or you'll never listen to your music again"
RSA keys should be 2048 bits long for a decent measure of security. Especially at smaller key sizes, it's not a very good encryption method.
http://en.wikipedia.org/wiki/RSA
As a side note:
At 128-bits, assuming the algorithm does not have a weakness, a brute force attack takes longer than the age of the universe. The amount of power that such an attack would require is also quite staggering.
At 256-bits, brute-forcing would require being able to harness the entire output of a star (or stars) to power the computer needed to complete the task.
As long as no holes are present in the encryption method, a 1024 bit key is (in practice) unbreakable.
http://en.wikipedia.org/wiki/Brute_force_attack
The last version was eventually "cracked", because the virus used the same key for all the encrypted files so once someone paid up they could distribute the key.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Also, this is one of the benefits of a journaling filesystem (or in OSX, "Time Machine"), among other things. Roll it back, and *poof* - no more encrypted files.
Quo usque tandem abutere, Nimbus, patientia nostra?
...the Casino Virus. Perhaps because of the similar concept of "holding data hostage".
The virus takes your FAT and stores it in RAM. Then lets you play a slot-machine game. If you win, you get your data back. If you lose, you lose your data. Some other combination of characters (in the slot machine) gives you the virus-writer's phone number.
Vivin Suresh Paliath
http://vivin.net
I like
This is data ransom, not blackmail.
But seriously, have you looked at FUSE lately? There's a filesystem for everything... And, historically, there are log-structured filesystems, which can, indeed, roll back any change that hasn't already been overwritten. That approach has nothing to do with inodes -- in fact, not all filesystems even have inodes.
A little knowledge is a dangerous thing. Version control software and/or backups are designed for this purpose - and are filesystem agnostic (work with whatever fs suits your needs). As a philosophy, yes, they're FS agnostic. In reality, it depends very much on which you choose. What you probably want is incremental backups -- version control is nice, too, but it's mostly to protect you from yourself.
Don't thank God, thank a doctor!
Fortunately, brute force attacks aren't necessary. If one can read the memory space used by the 'decryptor' one can find the key in seconds.
this is why movie content will 'never' be immune to cracking. in the case of this virus, the decryptor is sent to you over the internet, if you pay the money, but having a good backup scheme also defeats the need to brute force. having a good security setup, should negate even the need for backups to prevent infection in the first place.
so always have a competent hardened firewall device like smoothwall express, never download attachments (webmail helps a lot in this arena, along with a secure browser, and a phishing aware user/browser add-on) avoid windows like the plague, but if you must run windows make sure it can only get access to the actual ports of the programs you actually use on it. and never run as administrator, unless you really genuinely need to do something that can't be done as a normal user.
trusting a 'commercial' 'hardware' router to protect a windows machine is insane, even if you've replaced the firmware with some variant of linux, it's Still Not hardened like smoothwall...
fine if you have all linux/bsd machines, but windows has as much security as the emperor had new clothes, even with a $$$ security suite. sad but true, only 0% of tested windows security software could stop 50/50 2006/2007 known rootkit/malware post install... the best was i think being able to remove 7/50 and 13/50, if it had actually gotten installed. specialized tools were also tested, not just suites.
the point being, if you must run windows remember that a piece of paper stands more chance of surviving a nuclear blast at point blank than windows has of being de-rooted without a format.
https://www.gnu.org/philosophy/free-sw.html
http://en.wikipedia.org/wiki/Ransomware_(malware)
The crypting your files and extort has been around since 1989 http://en.wikipedia.org/wiki/PC_Cyborg_Trojan
As it was pointed out by another poster, no 1024-bit RSA is not sufficiently strong. Recent papers have demonstrated that factoring a 1024-bit key is now within practical reach. See for example this PhD dissertation from a student whose advisor was Shamir (the S in RSA FYI), which estimates that cracking a 1024-bit key would cost a few million US dollars.
Sure, at this point only a small number of organizations have a few million dollars to spare on cracking RSA, but this is beyond the point. The flaw is sufficiently serious that security standards are now recommending 2048-bit RSA keys minimum.
What I am talking about are relatively recent developments, it is not very well-known that 2048-bit is the minimum recommended length. This is why 1024-bit keys are still wildly used everywhere. My bank (www.wellsfargo.com) uses a 1024-bit key...
I thought of a virus along this line, but slightly different. What it would do is encrypt the data, decrypt on the fly until it is time to demand payment. All backups would have been encrypted too, if you have the correct hooks into the OS. I never tried it, since the dark side has a strong pull.
Fight Spammers!
Oops, I see you said "decryptor." Of course, if you have that, then you've unlocked this key. But, how many keys does the virus have on its keyring and how quickly does it acquire more? It's not like it's a DVD, fixed in a medium or a CSS descrambler ASIC in a $20 DVD player.
Program Intellivision!
in Nigeria?
There are real banks in Nigeria, owned by the ruling ethnic group, that's where the billions of dollars from oil goes. The rulers get their money while those who live where the oil comes from, the Niger Delta, have to fight for scraps.
FalconShould there be a Law?
But there are shortcuts to factorization. ie, if a long number ends in 0 or 5, it is divisible by 5. If the digits add up to 9, it is divisible by 9, etc. There may be similar but far more obscure shortcuts for larger primes.
Now, I am not a cryptanalyst or mathematician, and I'm not clear on how RSA works, so bear with me. Suppose I were to generate a list of prime numbers. This only has to be done once. Now suppose I take each prime and multiply it by every other prime on the list. Now if there are n primes, there are going to be n^2 products. Let's say we only store the last ten digits of the product, along with which primes generated it. There's only going to be a handful of primes who's product gives those same last ten digits. So, if the RSA depends on being able to decide which primes a large number is composed of, then would I not just have take the last ten digits of the large number, look up in my table to find the handful of primes that could multiply out to that, and just check those?
When our name is on the back of your car, we're behind you all the way!
I'll append a sarcasm tag next time. By the way, that bit of info is insanely depressing, and kind of made me feel a bit insensitive. Mod parent up.
The self-support model that is required for a zero-price Linux distro is often not acceptable in a corporate environment (unless they have internal IT that can provide the support). Which is why Red Hat Linux (and Suse and Oracle) continue to sell despite the existence of Centos. The best part is - while the price is non-zero (and generally too hefty for home use), the freedom is still included.
Most people aren't going to have more than a hundred gigs or so of storage in their computer in the first place. Given a halfway-decent backup system -- one which uses hardlinks, as I mentioned before -- and yes, the OS might take half of the backup drive. It will not, however, need an additional half every incremental backup -- only every time the OS changes.
As most people aren't causing terabytes worth of change, it should be no problem to have many backups (as in, every day for the past few months) on a single, dirt-cheap external hard drive.
Don't thank God, thank a doctor!
This makes it a little too easy:
/.
/.
1. Follow the money trail to the asshat (probably based in China or Russia).
2. Post the info on
3. I lead a mob of bored geeks to go beat the mustard out of this punk (and get the private key)
4. decryption algo posted on
5. everyone laughs at you, but at least you get your data back, and I get to crush someone's skull. everyone wins!
-Billco, Fnarg.com
...easy-to-use backups, and/or the government tracking down the payments and busting the guy who receives it.
Of course, if you are just backing up to the hard drive, the virus will make sure to trash your backups. Better back up to a non re-writeable CD. Most people's unique data isn't that large. If it is, you should be doing nightly offsite backups anyway.
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
I was waiting for somebody to mention this. Shadow copies, also known as Previous Versions, is a great way to undo this kind of thing (at least long enough to take a backup before reformatting, unless you're 100% sure you can purge all the malware). It's worth mentioning that they are also on Windows Server 2003/2008.
So, the answer is yes, but only for a limited time. The number of shadow copies that can be kept is determined by the "free" space on the drive. On the other hand, there's usually at least several revisions there, so if the folder isn't changed often you can probably find the old version. If the folder IS changed frequently, you'd probably notice right away.
I say folder because if a file's name is changed (or a file is deleted), you need to recover it by going to the folder's shadow copy and restoring from there (you can restore the whole folder, but can also extract individual files). You can also rename the file and check for shadow copies under its original name.
Finally, don't forget that the shadow copies can be deleted. It takes more than normal permissions - I don't think even normal Administrators can delete them directly, though if you have Administrator it's easy enough to get System - which means you would need to have approved a UAC prompt somewhere - but that's true of most software installation. That said, the actual attack (encrypting personal files) requires no special permissions at all - it would work even on a properly locked-down Linux or OS X box. IE under Protected Mode wouldn't have sufficient permissions, however.
There's no place I could be, since I've found Serenity...
Anyone heard about Onehalf? We're talking something like 1992-94 IIRC. :)
If my memory serves me right even further, the virus is from Kosice, Slovakia. It spread quite quickly (even though there was essentialy no Internet at that time in Slovakia) but later on, I believe ESET produced a utility to detect it and clean it up. Nice thing was, that it did not need to boot from clean boot floppy in order to do the clean-up (which was quite unussual at that time).
Funny thing then was, that few month later, as we though that Onehalf is - thanks to that utility - dead and old news, story came from USA that Onehalf reached there and that after a lot of trouble Norton was able to detect it. But not clean it. What a joke. If we've had email, we would happily mass-mail that ESET's anti-Onehalf utility to every one.
Maybe further info: ESET's One Half entry.
hany
Banking in Nigeria is not significantly less reputable than anywhere else.
The problem with Nigerian scams is because there are a lot Nigerians, and a significant fraction of them do not trust random people they don't know from Adam (or in some cases, members of their own family) and think that "europeans" must be a bunch of illiterate cretins if they are willing to believe things they read in random e-mails from strangers, and hence deserve to be scammed.
The main factor in Nigerian fraud, is that part of the Nigerian population that believe that God created cretins so they could be scammed. Not a very christian beliefe:
Yes its true, Christianity would stop Nigerian scams - send more missionaries :-)
Yes, I have been to Nigeria.
Sent from my ASR33 using ASCII
I know there will always be people who don't believe "in" enlightened self-interest, but it is not in your own self-interest to deliberately (How should I put this politely?) defecate in your own water supply.
You started by playing around with the scripts that the real blackhats built and left lying around. Then one of them contacts you (Because he naturally left a call-home in your script and has been "keeping an eye on you" -- but not much of an eye. Don't kid yourself.) and suggests you help him collect a bot army.
Now you've learned how to get a bot army, and you have a small army of your own. Trouble is, small armies aren't profitable. So you start the moving from script-jockey (The blackhats don't want to insult you, so they don't call you kiddie to your face.) to script-remodeller. But you have to eat, so when your blackhat suggests you try a little extortion, it sounds interesting.
What he doesn't tell you is that he is leading you to run interference for him while he goes after bigger fish. He tells you how to get into some foreign bank and set up accounts that have a very ephemeral existence, then stands back and watches you, and waits for you to either prove you're on top of this game or get arrested.
In the meantime, the money you are sucking out of the economy is not available to do the kind of dev work you'd prefer.
You lose.
Intelligent?
Computer memory is just fancy paper, CPUs just fancy pens with fancy erasers; the 'net is just a fancy backyard fence.
The main factor in Nigerian fraud, is that part of the Nigerian population that believe that God created cretins so they could be scammed. Not a very christian beliefe:
Yes its true, Christianity would stop Nigerian scams - send more missionaries
I can't help but notice that if you are correct, what might help them even more is not believing in silly propositions like "God" and "Christianity."