British network O2 sent its business customers USB pens as a marketing ploy. The only problem was that some of the devices contained malware. They were encouraged to use the pens to download a free eBook.

O2 sent out an email "Urgent: Information about potential virus" warning about the foul up. They warned that out of date anti-virus software may not pick up the infection.

The message also warned that anyone running a server could possibly infect any visitors. "The virus has the ability to install new programs onto your system including updated versions of itself and programs that might grant the virus’s author remote control over your computer."

The email went on to say: "If you have already [used the device] and your antivirus has flagged a risk, please follow the instructions your antivirus software gives you and then remove and dispose of the USB."

The malware only affects these systems: Windows 2000, Windows 95, Windows 98, Windows ME, Windows NT,Windows Server 2003, Windows Vista, Windows XP.

An O2 spokesman said: "For any customers that have already used the USB or are concerned, we have a specialist team on hand to support them and guide them through any action they may need to take. We apologise for any inconvenience."
However, O2 customer data has recently been put up for sale on the dark web. The company denies that it has been hacked.
Source: The Register