A miscreant claims to have broken into Capgemini and leaked a large amount of sensitive data stolen from the technology services giant – including source code, credentials, and T-Mobile’s virtual machine logs.

The French multinational IT and consulting firm did not immediately respond to The Register‘s request for comment, and has yet to formally confirm or deny the cyber-criminal’s claims. We will update this story if and when a spokesperson replies to our inquiries. We had heard rumblings of a recent security breach at Capgemini, which earlier declined to comment on those rumors.

According to a BreachForums post today announcing the leak, a crook who goes by “grep” said they allegedly compromised Capgemini this month and swiped 20GB of data from the biz. This is said to include some databases, source code, private keys, credentials, API keys, projects, employee data, and other information.

In portions of the leaked information reviewed by The Register we could see lists of Capgemini employees with what looks like their names, email addresses, usernames, and password hashes. There were also what appeared to backup archives, and files related to Capgemini clients, including internal configuration details for their cloud infrastructure.

“They had more data but I decided to exfiltrate only big files, company confidential, Terraform, and many more,” the thief wrote. As well as offering the stolen data to fellow forum users, grep also shared some select samples, including what’s said to be T-Mobile VM logs. Screenshots of the allegedly stolen data posted on X appear to show customer info.

Capgemini generated more than €22 billion (about $24 billion) in revenue in 2023.

In July, the consultancy won a controversial UK government contract worth up to £574 million.

Under the lucrative deal, valued between £403 million and £574 million, Capgemini will run legacy tax management systems for His Majesty’s Revenue and Customs until 2029.

Both of the services in the contract, Enterprise Tax Management Platform (ETMP) and Enterprise Operations (EOPS), run SAP ECC 6.0, a legacy system from the German software giant that exits mainstream support at the end of 2027. ®