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Local and federal officials are investigating how a hacker managed to gain remote access to a Florida city water treatment plant in an unsuccessful attempt at what could have been mass poisoning.
A mysterious hacker infiltrated a computer for the water treatment system in the town of Oldsmar, near Tampa, and briefly increased the amount of sodium hydroxide, also known as caustic soda, by a factor of more than 100, the sheriff from Pinellas County, Bob Gualtieri, said on Monday.
The chemical is used in small amounts to control the acidity of water, but it is also a corrosive compound commonly found in household cleaning products, such as liquid drain cleaners. In large quantities it can cause irritation, burns and other complications.
An insightful supervisor noticed the chemical’s measurements suddenly changing wildly on his computer screen and promptly stepped in to reverse the action, leaving the city’s water supply unchanged, the Tampa Bay Times reported.
This is, honestly, one of the most disturbing things I’ve ever seen. A caring civil servant saved the city from … mass poisoning. https://t.co/aufA0oEtnr
– Chris Hayes (@chrislhayes) February 8, 2021
The hack occurred on Friday and the unknown suspect managed to breach Oldsmar’s computer system and briefly increased the amount of sodium hydroxide from 100 parts per million to 11,100 parts per million, said Gualtieri.
“At no time has there been a significant adverse effect on treated water,” said Gualtieri, adding: “It is important to note that the public was never in danger.”
A factory worker noticed the unusual activity for the first time around 8 am on Friday morning, when someone quickly accessed the system. At around 1:30 pm, someone accessed it again, took control of the mouse, directed it to the software that controls the water treatment and increased the amount of sodium hydroxide.
Authorities said other safeguards in place would likely have detected the change before it reached the water supply. The remote access system that the hacker was able to use has been disabled.
The targeted treatment plant provides water for companies and about 15,000 residents, said Gualtieri.
The sheriff’s office, the FBI and the Secret Service are investigating.
No one was arrested, although investigators have some clues. Other municipalities in the area have been alerted to the attack.