In a post on Twitter, the city stated that it had detected a network breach and has taken appropriate actions to mitigate any potential effects.
"The City of Johannesburg has detected a network breach which resulted in unauthorised access to its information systems," the city said.
"The incident is currently being investigated by City of Joburg cybersecurity experts, who have taken immediate and appropriate actions to reinforce security measures and mitigate any potential impacts."
Following the hack, a number of systems have been shut down by the city as a precaution, including its website, e-services, and billing system.
The investigation is expected to take 24 hours, and the city said customers will not be able to transact on e-service or log queries on its systems for this period.
Ransom note
The Business Day reported that City of Johannesburg employees received a ransom note from a group named the Shadow Kill Hackers.
"All your servers and data have been hacked," the note said. "We have dozens of back doors inside your city."
"We have control of everything in your city. We also compromised all passwords and sensitive data such as finance and personal information."
The attackers reportedly demanded a ransom of 4 bitcoin (around R435,000) to be delivered to a specific address by 28 October. If this is not delivered, the attackers said they would upload all the data onto the Internet.
The report also stated that major local banks were affected by the cyber attack, attributing yesterday's online banking downtime to the hack.
The City has detected a network breach in its systems ^TK pic.twitter.com/r43iiJiUya
— City of Joburg (@CityofJoburgZA) October 24, 2019
