The blast at the home of former defence ministry general secretary Yiannis Sbokos, in the affluent suburb of Kifissia, damaged the front door and broke some roof tiles, ANA said yesterday.
Early reports suggest dynamite was thrown at the ex-officials house.
Sbokos in October was sentenced to 16 years in prison as an accessory to laundering money from arms purchases bribes.
He was a close associate of 73-year-old former defence minister Akis Tsochatzopoulos, who received a 20-year sentence in the same case, relating to purchases of armoured vehicles, submarines and anti-aircraft missiles between 1996 and 2001.