The attack temporarily reduced Tehran's means of targeting shipping traffic in the Persian Gulf, says The New York Times.
The attack was reportedly in response to Iran downing a US drone.
A database used by Iran's paramilitary arm to devise attacks against oil tankers was wiped out by a US cyberattack in June, temporarily reducing Tehran's means of targeting Persian Gulf shipping traffic, according to a Wednesday report from The New York Times.
Iran is trying to bring military communications networks back online and recover information lost in the attack against the Islamic Revolutionary Guards Corps, the Times said. The attack, part of an unspoken cyberwar between the US and Iran, was in response to Iran shooting down a US surveillance drone it said was violating Iranian airspace, the Times reported.
"As a matter of policy and for operational security, we do not discuss cyberspace operations, intelligence, or planning," a Department of Defense spokeswoman said in an email.
US Central Command had no comment.
Originally published Aug. 28.
Update, Aug. 30: Adds response from the Department of Defense.