Security News

Hacker Alters Chemical Levels at US City's Water Treatment Plant

In something resembling a movie plot, a hacker has remotely gained access to the water treatment plant in the Florida city of Oldsmar and briefly altered the level of chemicals entering the water.

"The hacker changed the sodium hydroxide from about 100 parts per million to 11,100 parts per million, said Oldsmar Sheriff Bob Gualtieri during a press conference (image below). "This is obviously a significant and potentially dangerous increase."

(Sodium hydroxide, aka lye, is used in small amounts to control the acidity of, and remove metals from, drinking water. It is also an ingredient in household products such as liquid drain cleaners. Contact with sodium hydroxide can cause skin irritation, burns and hair loss, while ingestion can be fatal.)

Luckily, the actions of the hacker were spotted by an alert employee at the plant, who noticed the cursor on a computer screen moving as the hacker attempted to access software used in monitoring chemical levels. The hacker managed to alter the chemical levels and then disconnected, at which point the employee immediately reset the levels, potentially saving a catastrophe.

Despite the intrusion, which happened on Feb. 5, city officials confirmed that no affected water made it to the city's 15,000+ residents.

"The protocols that we have in place, monitoring protocols, they work — that’s the good news," said Oldsmar Mayor Eric Seidel. "Even had they not caught them, there (are) redundancies in the system that would have caught the change in the pH level."

Investigators are unsure who was behind the attack or from where it originated but, if caught, those involved will face state felony charges and, possibly, federal charges.

*Watch press conference with Oldsmar Sheriff Bob Gualtieri.

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