Iran’s President Mahmoud Ahmadinejad says Stuxnet worm hit centrifuges used to enrich uranium at Iran’s nuclear sites. Iran had previously confirmed that the worm affected systems in the country, including non-critical systems at a nuclear reactor. Security researchers now believe that St.uxnet had at least two targets, including a turbine at Bushehr reactor. The worm is designed to slow down and then speed up centrifugees, either ruining the uranium being refined or stressing the devices so much that they break.”]
Source: https://www.csoonline.com/article/2126203/report–iran-confirms-stuxnet-hit-centrifuges.html