“In the recent war, those who had information and were of interest to Israel were easy prey for hacking,” former minister Mohammad Javad Azari Jahromi said. He did not identify those targeted.
"WhatsApp has low resistance to cyberattacks and low security, and Israel has used this tool," he added.
He said that using WhatsApp for exchanging confidential information was not permitted for officials and military personnel.
His remarks come as Iranian authorities face scrutiny over security lapses following the assassination of senior commanders in June during the war with Israel.
Mahdieh Shadmani, daughter of slain commander Ali Shadmani, has publicly disputed official claims that mobile applications exposed locations that led to Israeli strikes, saying her father carried no smart devices.
“My father’s location changed every few hours. He carried no smart devices or phones. Security protocols were followed, yet during his time commanding the war headquarters, he was repeatedly targeted for assassination by Israel,” she said on July 4.
Jahromi's comments come two months after Israel launched a surprise military campaign on June 13 targeting military and nuclear sites, killing hundreds of military personnel, nuclear scientists and civilians.
The Islamic Republic says 1,062 people were also killed by Israel during the conflict, including 786 military personnel and 276 civilians.
Tehran responded with missile strikes that killed 31 civilians and one off-duty soldier, according to official figures published by the Israeli government.
On June 22, the US carried out airstrikes on Iran’s key nuclear sites at Fordow, Natanz, and Isfahan. A US brokered ceasefire came into effect on June 24, which ended the 12-day air war.