( CNN ) -- Iran has been targeted by a new computer worm named Stars , according to an Iranian official . `` The damage is very slight in the initial stage , '' defense official Gholam Reza Jalali told the semi-official news agency Mehr . It was unclear how long ago the worm was discovered or which systems in Iran it was designed to penetrate . `` It is compatible with the ( targeted ) system , '' Jalali said , and `` it is likely to be mistaken for executable files of the government . '' The announcement comes less than a year after Iranian nuclear facilities were targeted by a highly specialized computer worm called Stuxnet . It was apparently designed to secretly infiltrate the centrifuge machines that refine uranium and make them spin so fast they would break , according to David Albright of the Institute for Science and International Security . `` About 10 % of the centrifuges were destroyed by Stuxnet , '' he said , which resulted in a setback for the Iranian nuclear program by as much as a year . Iranian officials have said they believe last year 's Stuxnet cyberattack originated in Israel and the United States , but officials from neither country have commented on the malware 's origin . An American and an Israeli representative reached by CNN about the latest report again declined to comment . An official with Symantec , a computer security firm that decoded the Stuxnet program last year , said a sample would be required for the company to forensically study the latest program for clues to its origin and its target . `` Until we have that , we can only guess at this point , '' said John Harrison , with Symantec 's security response group . An Iranian official at the United Nations , Alireza Miryousefi , said he could provide no further details on the latest attack . But in a statement , he said , `` These sabotages -- ( such ) as producing computer viruses and the assassination of our nuclear scientists -- are outright criminal and illegal , aimed at preventing Iranians from implementing their peaceful nuclear rights . '' Last year , in addition to the computer worm attack , two Iranian nuclear scientists were attacked by unknown assailants with car bombs . One of them was killed . Albright warned that the latest cyberattack on Iran could prompt a response . `` Iran does n't usually take things lying down , '' he said . `` I 'm sure they will start thinking about retaliation . They 'll probably think of trying to launch a cyberattack . '' CNN 's Brian Todd and Pam Benson contributed to this report .
The announcement came less than a year after Iranian nuclear facilities were attacked . At the time a new worm appeared to be on Iran 's nuclear production capability . The announcement left unclear which facilities are targeted by the new worm .