The malware was identified as W32.TGammima.AG, a worm originally designed to steal passwords for online games.
It seems that this is not the first incident of its kind. NASA admitted that security slip ups do occur every once in a while, although they continue to be rather rare:
"This is not the first time we have had a worm or a virus," a NASA spokesman told Wired News. "It’s not a frequent occurrence, but this isn’t the first time."
And it won’t be the last time, that’s for sure. Good thing that the infected machines were not running critical processes. Or so NASA claims.