The soaring value of the Bitcoin digital currency has resulted in increasing criminal attention, with more than 100 families of malware now attempting to steal—not only Bitcoins—but more than 40 other crypto-currencies, according to a research report released on Feb. 26 by Dell SecureWorks.
So-called crypto-currency stealing malware (CCSM) searches for and steals the wallet file that stores the victim's encryption keys, transferring it to a remote server and creating a transaction to transfer the money to the thieves' account. Adding functionality to steal alternative currencies, colloquially referred to as altcoins, isn't technically challenging, Joe Stewart, director of malware research for Dell SecureWorks, a managed security service provider, told eWEEK.
"Writing a program to steal a single file on the hard drive—let's face it—is not difficult," Stewart said.
The research, released at the RSA Conference the same week that the popular Mt. Gox exchange shut down operations following a massive online attack and allegations of financial impropriety, underscores the risk in dealing with the popular, yet still-immature currency system. Two weeks ago, Mt. Gox began delaying withdrawals to allegedly divine the nature of technical issues. On Feb. 24, the popular Bitcoin exchange halted all trading.
"As there is a lot of speculation regarding Mt. Gox and its future, I would like to use this opportunity to reassure everyone that I am still in Japan, and working very hard with the support of different parties to find a solution to our recent issues," Mark Karpeles, the CEO of the trading group, said in a statement that replaced the Mt. Gox Website.
While specific exchanges have had difficulties and suffered attacks, the currency itself has remained quite strong. So much so, that a variety of alternative currencies have cropped up based on the same code that makes Bitcoins work as a decentralized currency. About 9 percent of CCSMs also targets the next most popular crypto-currency, Litecoin, according to Dell SecureWorks.
"Even though none of these altcoins have approached the per-coin value of Bitcoin, some have achieved the total market caps measuring in the millions of dollars," the company's research report stated. "As a result, these altcoins have also been targeted for theft."
The most popular CCSM is PredatorPain, accounting for one-third of all attacks and costing $35 on the hacker underground to purchase, according to Dell SecureWorks.
Enterprises and users that deal with Bitcoins should not trust a computer system to be free of malware, but instead use a hardware wallet device to take the crypto-currency transaction away from the reach of malware, SecureWorks' Stewart said.
"The keys were never on the computers and there is no way for the thief to steal the keys off the hardware wallet," he said.