The Russian government turned Kaspersky Lab's anti-virus software into a tool for espionage. This is written by The Wall Street Journal with reference to informed sources.
The newspaper points out that, with the consent of the company, modifications were made to the anti-virus software that allow to search for secret files on the users' computers. In particular, the antivirus searches in documents for the words "Top Secret" or the numbers of secret US programs.
In Kaspersky Lab, they denied involvement in such a modification and expressed their willingness to interact with the US authorities.
Earlier the newspaper wrote that Russian hackers allegedly stole the secret materials of the NSA using Kaspersky's antivirus.