Cryptolocker

Until today, Microsoft Windows users who’ve been unfortunate enough to have the personal files on their computer encrypted and held for ransom by a nasty strain of malware called CryptoLocker have been faced with a tough choice: Pay cybercrooks a ransom of a few hundred to several thousand dollars to unlock the files, or kiss those files goodbye forever. That changed this morning, when two security firms teamed up to launch a free new online service that can help victims unlock and recover files scrambled by the malware.

A small US law firm has bravely admitted losing its entire cache of legal documents to the Cryptolocker Trojan despite attempting to pay the $300 (£180) ransom in a bid to have them unscrambled.

According to TV reports, Goodson's law firm in the North Carolina state capital Charlotte became the latest victim of a malware menace that was custom-written to lever ransom money from precisely this type of relatively cash-rich but time-poor firm.

Criminals running the Cryptolocker scam have become the latest victim of the Bitcoin bubble.

New versions of the malware have been shown by anti-virus firm F-Secure as having a lower ransom demand than previously.