A new Ransomware kind of attack

This describes a new kind of IT ransom which should be much more professional and profitable.

The attacker manages to access some company’s servers, then encrypts the data in the databases but he modifies the DBs access routines to encrypt/decrypt on the fly all data with his own encryption key. In this way for the company all continues to work. He then waits a few months so that all DB backups are encrypted with his keys and at this point deletes the encryption keys from the company’s systems and asks for a ransom to give it back.Notice that backups are unusable because they too are encrypted with the attacker key.

Obviously, strong IT security procedures should prevent and detect this, from off-line testing of backups to intrusion detection.

On Cryptolocker and the like

Cryptolocker and similar malware are getting more and more common. The latest versions that appeared work on also Android (one id called Simplelocker). In general what they do is to encrypt some or most of the files on your PC, tablet or smartphone, in particular text, sound, images and video files, which of course includes all your music video library.

Been a ransom, you are asked to pay some bitcoins (or similar untraceable currency) to get your files decrypted.The only defense, a part from keeping your PC clean, up-to-date, with good anti- … whatever … and being very careful on what you click and the email you open, is to keep very updated backups. Indeed once you get infected and locked / encrypted, there is absolutely nothing that you can do to decrypt the files (unless of course if you pay).

The only precaution is to have good and recent backups, and start all-over again from scratch.

But there is a very important point to remember here, not all backups are equal! Good backups are only those done on off-line media, like dvd, blu-ray disks, external usb disks that are connected only for the time of making the backup, and so on. In technical term it is often called an air-gapped backup, that is a storage that you cannot usually access from your device. This excludes most of the Clod storage and backup systems!

The reason for this is that if the backup is on a continuously or very often connected device, and the backup is done automatically as soon as new data is on your device, when the ransomware encrypts your file, the encrypted version is automatically copied on the backup device substituting the original data, and you can end up having also the backup data encrypted.

Note Added: Simplelocker is more a proof-of-concept than a real malware, in these two posts [1] and [2] Simon Bell describes the malware and how to decrypt the files.

Game Over Zeus and Banking Malware

This announcement by US-CERT made me think about the current status of the war (I think that at the moment this is actually the correct word) between attackers / thieves / fraudsters and ICT Security practitioners, Banks, FInancial Institutes etc.

Recently we have seen banking malware using Tor hidden services to hide C2C (Command-and-Control) servers, or as described in the US-CERT announcement, P2P (peer-to-peer) networks. The purpose is the same, to hide the controlling master of the malware, that is the attacker / thief / fraudster her/himself. This also means that recently security practitioners, law enforcement and bank personnel got very good in finding and at least disrupting the C2C servers, otherwise there would be no need to find new ways of hiding them.

But how is this war going, that is, who is winning? Let’s be clear, we, the good guys, are losing.

At first sight the reason for this is simple: there are just too many bugs in today’s software (and possibly in hardware, or at least in embedded software in hardware) and new bugs are added at such a rate that our efforts to ‘secure’ the software are improving the situation a little but not much. It is just a never-ending chase: find a bug, exploit the bug, fix the bug – repeat… It is true that bugs are getting more difficult to find, that software developers are getting better in writing software and fixing bugs, that Bugs-Bounties are awarded to bugs discoverers from software houses etc., but the same happens on the other side and a real market of exploits (to which even secret services and the like participate) of unknown (also called 0-day) bugs exists and flourishes.

In this situation the approach that it is often adopted to protect financial transactions online (web-based) is to balance the costs of defensive measures with the losses to attackers. In the losses one should consider both those direct and those indirect, like bad publicity and loss of customers. Investing too much in some defensive measures could work but could also be a waste of money since the next attack can just avoid the expensive defensive measure and exploit some other bugs or flow in the process or, even worse, human weakness.

This really looks like a never ending cat-and-mouse game.

News of the week

Some news of this week that caught my eye:

  • A claim for a new “indestructible” rootkit: BadBIOS: true or advertisement? See here.
  • Lavabit and Silent Circle join forces in the Dark Mail Alliance to create a really secure end-to-end email service. See here.
  • Amazon will build a 600M USD cloud for the CIA, IBM is not too happy about that… See here.
  • Bitcoin “crisis” and the advent of Litecoin, what is it going on in the world of online currencies? See here for a report and here for the latest news.