Iran tried to increase chlorine levels in the water flowing to residential areas during April’s cyberattack against Israel’s water systems, a Western intelligence official told the Financial Times.
The FT report published on Monday cited the source stating that hundreds of people would have been at risk of becoming ill and that the attack was close to being successful.
The head of Israel’s National Cyber Directorate hinted last week that the attack may have aimed to mix chlorine or other chemicals into the water supply.
Additionally there was a chance that the attack would have triggered a fail-safe, shutting down the pumps and leaving thousands without water during during the recent deadly heatwave in Israel.
The Western official and four Israeli officials, who were all briefed on the attack and all remained anonymous, told the FT that the Iranians hacked into the software that runs the pumps after routing through American and European servers to hide the source.
The Western official said: “It was more sophisticated than they [Israel] initially thought… It was close to successful, and it’s not fully clear why it didn’t succeed”.
An unnamed Israeli official told the Financial Times that the attack created “an unpredictable risk scenario” by starting a tit-for-tat wave of attacks on civilian infrastructure, something both countries have so far avoided.
Last week, Israel’s national cyber chief Yigal Unna described the hack as a “synchronised and organised attack” aimed at disrupting key national infrastructure.