Eskom denies its live customer database has been exposed online - but the security specialist who found it disagrees

South African utility giant Eskom has denied claims made earlier this week that its live customer database - including payment details, such as credit cards - has been exposed on the internet.

Responding to complaints from security specialists in South Africa, the company's acting CIO, Nondumiso Zibi, claimed that Eskom's investigations prove that the database "does not belong to Eskom and is not hosted on our network".

He added: "We have traced it and can confirm that it is hosted in the US. We have managed to trace the company responsible for this server and the database. The company is very co-operative and has since confirmed that the server has been shut down."

The company, he continued, is conducting further investigations to determine whether the data in question is valid and belongs to Eskom customers.

I never even gave them an IP of a server. How would they know which one?

— stoXe (@DevinStokes) February 7, 2019

But the security specialist who went public with the alleged compromise, Devin Stokes, described the company's explanation as nonsense - not least because he never provided Eskom with the IP address of the exposed MongoDB database.

"They had live payment records populating the database for electricity customers," he tweeted, pointing out that no-one from the company has bothered to contact him to find out more details about the exposed database.

He added that there are three likely explanations: "They left their database unsecured on an American cloud host, such as Azure or AWS (most likely); or, they got hacked and the data siphoned off (not likely); or, they sold the data to another company (no idea)..."

"I don't understand how your data being on someone else's servers, logging financial transactions through the mobile app in a live fashion is possible. Does that make sense to anyone else or am I crazy?" asked Stokes in response to Eskom's statement.