Interestingly, a seller going by the name of "madeinrm" had the price set at $5,000, while researchers from Trusteer came across what appears to be a different seller offering Carberp source code, but with a hefty $50,000 price tag, and said to be sold in coordination with the Carberp author.
Researchers from Trusteer suggest that a "breach of contract by a Carberp seller could have caused a buyer to take revenge and sell the source code.
Earlier this year, Russian authorities claimed to have captured the mastermind behind the Carberp banking Trojan and other members of the criminal gang. The cybercrime ring, led by a 28-year old Russian national, allegedly has been in operation since 2009 and has stolen approximately $250 million. In March 2012, authorities arrested and broke up a gang that used Carberp to steal $2 million from over 90 individual bank accounts.
It's very likely that once the code is sold, the new buyers would add on new features and distribute those variants to create newer versions of sophisticated malware."
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