Software piracy isn't just a licensing problem, it's a security problem, the Business Software Alliance said in its annual piracy report this week.

The BSA, which represents the commercial software industry and spearheads the effort to stop the spread of unlicensed applications, estimates in its Global Piracy Study 2010 that some $51.4 billion of unlicensed software was distributed in 2009.

"This means that for every $100 worth of legitimate software sold in 2009, an additional $75 worth of unlicensed software also made its way into the market," the report states.

Aside from the cost to the software industry, the report says, the high rate of piracy may be contributing to the spread of malware.

"Despite the connotation, unlicensed PC software is not necessarily 'free,'" the report says. "It takes effort to obtain, and it usually requires more support than legitimate software, since it does not come with a steady stream of updates and patches, and may, in fact, contain malware."

The report makes reference to a previous study by IDC, which revealed that "one in four websites that offered pirated software or counterfeit activation keys attempted to install infectious computer code, like Trojan horses and key loggers, on test computers. Even more striking, 59 percent of the counterfeit software or key generators downloaded from peer-to-peer (P2P) sites contained malicious or unwanted code."

The study also found the cost of recovery from a security incident resulting from pirated software on a PC can cost more than $1,000, often exceeding the cost of legitimate software, the BSA says.

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