Version of Target Malware Linked to Young Russian

Cybercrime Researchers Say Rinat Shabaev Offered to Sell Copies of Virus.

Security experts believe the malicious software that infected Target Corp. was in part the work of a 23-year-old in southern Russia who counted punk rock as a hobby.

Rinat Shabaev, who lives in southern Russia, offered to sell copies of a version of the computer virus used against Target for $2,000 apiece, according to three security researchers who track Russia-linked cybercrime.

The researchers said they traced an earlier version of the software to Mr. Shabaev via digital footprints, including a user name—Ree4—that was associated with listings to sell the software, as well as an email address on Mr. Shabaev’s page on VK, the Russian equivalent of Facebook.

Mr. Shabaev hasn’t been accused of any wrongdoing, and writing such software isn’t in itself illegal. He discussed his role in the software Tuesday in a video interview on Lifenews.ru, a Russian news site. He said in the video he didn’t invent the software, which skimmed credit and debit card data when entered at cash registers. But he said he did write an extension that enabled the program to save credit-card data and stash it on a server—an improvement security experts say helped the program to work undetected at Target.

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