Computers inside Pfizer’s network have been busted sending out spam touting its flagship drug Viagra’s effectiveness, not to mention ads for cheap Rolexes and shady junk stock. According to Wired,

Pfizer’s computers appear to have been infected with malware that has transformed them into zombie computers sending spam at the behest of a hacker.

Rick Wesson, CEO of Support Intelligence,a small San Francisco-based security company that alerted Wired News to the problem, believes that

Pfizer computers have been spamming inboxes for the last six months and that he’s kept 600 spam messages sent from company computers. He says 138 different Pfizer IP addresses have been blacklisted by various groups, but adds that he can’t estimate the number of infected machines without more information or installing monitoring equipment on the edge of Pfizer’s networks.

Despite several warnings from Support Intelligence, Pfizer has been reticient to acknowledge the problem. According to Pharmalot,

On Tuesday morning between 7 a.m. and 10 a.m., Pfizer’s network sent at least 20 messages about sex and penises, according to Wesson. The number of infected machines is impossible to determine, because much of the traffic comes from behind a firewall that obscures the machines’ internal IP addresses.

Hmmm … is it really the result of malware — or is this perhaps a black-ops marketing program within Pfizer?