Telstra Group (ASX:TLS) denied that its systems were breached by hackers as part of a cyberattack that also targeted Qantas Airways (ASX:QAN) and global software firm Salesforce, the Australian Financial Review reported on Thursday.

An international cybercriminal group updated its dark web ransom site to include the telecommunications firm, saying it would leak 100 gigabytes of personal information relating to users, per the report.

No passwords, banking details, or personal identification data such as driver's licenses or Medicare numbers were included in the data being presented by the hackers, a Telstra spokesman said. Based on the firm's assessment, "the data has been scraped from publicly available sources and does not originate from Telstra systems," the spokesman added.

The cybercriminal group had claimed to possess 19 million pieces of "personally identifiable information" relating to Telstra users from a hack in July 2023, including full names and addresses.

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