The website -- www.nsg.gov.in -- and some official e-mail domains of the force were corrupted recently in a suspected hacking attempt, NSG sources said.
The website domain has not suffered much damage and a technical probe has been initiated to identify the source of the attack which could have possibly existed outside the country, they said.
The passwords of the official emails of NSG units and officials are also being renewed to keep them safe, they said.
The NSG web portal hosts a number of facilities, including details of the tenders that the force procures for operational and administrative purposes.
The portal is maintained by the technical wing of the force based at the headquarters here, in consultation with the National Informatics Centre (NIC).
Recently, the official portal of the Central Bureau of Investigation (CBI) was also targeted by hackers.