Feeds

File-NUKING Cryptolocker PC malware MENACES 'TENS of MILLIONS' in UK

Back up before devil PC malware demands 860 BUCKS (530 quid)

Build a business case: developing custom apps

The infamous Cryptolocker malware, which encrypts your computer files and demands a payment of £534 ($860) to unlock them, may have been sent to "tens of millions" of Brits, Blighty's crime-busters warned today.

According to an alert from the UK National Crime Agency (NCA), a fresh round of ransomware-loaded spam posing as bank notices has been sent out, with small and medium-sized businesses targeted in particular. The messages, described as a "significant risk", carry booby-trapped attachments and claim to be official documents from financial institutions.

Lurking within the attachments is a Trojan called Cryptolocker that, when executed, silently installs itself and quietly begins encrypting documents one by one on the Windows PC using tough-as-nails AES256. When it's finished, it demands a ransom payment of 2 Bitcoins (at least 500 quid or 800 bucks) to decrypt the data, which must be paid within a time limit.

The software nasty is particularly fiendish: The malware first contacts its master's control server, which generates a new public-private 2048-bit RSA cryptographic key pair and sends the public half to the malware.

Then for every file discovered on the computer, Cryptolocker generates a new 256-bit key and uses it to encrypt that document using the virtually unbreakable AES256 algorithm. That AES key is then encrypted using the RSA public key and stored with the obfuscated document.

Only when the victim pays up does the Trojan download the private half of the RSA key, which is used to decrypt the per-file AES keys and ultimately restore all the protected documents. Targeted files include anything with .doc, .docx, .xls, .xlsx, .ppt, .pptx, .dwg, .dxf, .dxg and .jpg extensions and plenty more.

Users are urged to maintain regular backups of their data, kept separate from their computers, as the encryption is essentially uncrackable, and consider using tools to thwart the software nasty. The Trojan infects systems running Windows 8, Windows 7, Vista, and XP.

"The emails may be sent out to tens of millions of UK customers, but appear to be targeting small and medium businesses in particular," the UK's NCA said.

"This spamming event is assessed as a significant risk."

Cryptolocker's operators are also apparently developing a keen sense of economic opportunism, upping their Bitcoin demands at a time when the digital currency's exchange rate has never been higher.

While authorities have yet to finger any suspects behind the Cryptolocker epidemic, the NCA believes the operation is the work of a tech-savvy crime ring.

"The NCA are actively pursuing organized crime groups committing this type of crime," said Les Miles, deputy head of the NCA's National Cyber Crime Unit.

"We are working in cooperation with industry and international partners to identify and bring to justice those responsible and reduce the risk to the public."

In addition to installing and updating trusted security software, users and administrators can protect against infections by using best practices (read: common sense) such as avoiding links and attachments from unknown or suspicious sources and scanning all attached files for malware. ®

The essential guide to IT transformation

More from The Register

next story
Rupert Murdoch says Google is worse than the NSA
Mr Burns vs. The Chocolate Factory, round three!
e-Borders fiasco: Brits stung for £224m after US IT giant sues UK govt
Defeat to Raytheon branded 'catastrophic result'
Germany 'accidentally' snooped on John Kerry and Hillary Clinton
Dragnet surveillance picks up EVERYTHING, USA, m'kay?
Snowden on NSA's MonsterMind TERROR: It may trigger cyberwar
Plus: Syria's internet going down? That was a US cock-up
Who needs hackers? 'Password1' opens a third of all biz doors
GPU-powered pen test yields more bad news about defences and passwords
Think crypto hides you from spooks on Facebook? THINK AGAIN
Traffic fingerprints reveal all, say boffins
Microsoft cries UNINSTALL in the wake of Blue Screens of Death™
Cache crash causes contained choloric calamity
prev story

Whitepapers

Endpoint data privacy in the cloud is easier than you think
Innovations in encryption and storage resolve issues of data privacy and key requirements for companies to look for in a solution.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
Solving today's distributed Big Data backup challenges
Enable IT efficiency and allow a firm to access and reuse corporate information for competitive advantage, ultimately changing business outcomes.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.