Dell has been contacting certain customers directly in order to schedule service calls to replace motherboards that contain malware.

The malware, described elsewhere as spyware, was in the embedded server management firmware of replacement motherboards sent out for certain models of servers (see below for a list). [An earlier version of this story listed only the R410 as affected, but others are as well.] It's not yet clear at this point exactly what firmware was compromised nor what the specific spyware was.

Dell does say that the spyware is Windows-specific and that non-Windows systems are not vulnerable. New R410 systems are also not affected, just replacement motherboards.

Some other reports have described this as a "hardware trojan" of the sort that has been theorized recently, but it is not. This is malware embedded in firmware, and firmware is simply software in a ROM. It's only slightly unconventional.