CryptoLocker victims will now be able to save their encrypted files following the launch of a free service by security firms FireEye and Fox-IT.
Users can access a private decryption key by uploading an affected file to DecryptCryptoLocker, which is then used with software from the site to unlock files.
Darien Kindlund, director of threat intelligence at FireEye, said: "No matter the type of cyber breach that a business is impacted by, it is our goal to resolve them and get organizations back to normal operations as quickly as possible."
A form of ransomware, CryptoLocker first started infecting computers in September of last year, reaching a peak monthly infection rate of 155,000 the following month, according to Fox-IT.
Overall the virus is thought to have affected more than half a million machines, with English speaking countries the prime target.
Michael Sandee, principal security expert at Fox-IT, said: "In the end, 1.3% of victims paid a CryptoLocker ransom, therefore, a large amount of victims likely permanently lost files due to this attack."
The virus was distributed through the GameOver Zeus botnet that was taken down by international police for two weeks this June.
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Following the disruption the Federal Bureau of Investigation (FBI) claimed that the ransomware had been neutralised, a statement disputed by security firm Webroot, which said similar malware was still in circulation online.
