UK-based multinational telecom firm Colt Technology Services confirmed on Thursday that hackers have taken some data from its systems.
Colt provides network, voice, and other services to customers in Europe, Asia and the United States. The company announced on August 14 that some support services had become unavailable due to some systems being taken offline in response to a cyber incident.
The telecommunications firm said at the time that the internal system on which it detected the intrusion was separate from customer infrastructure. Colt has since been working on restoring impacted systems, but some services, such as Colt Online and its Voice API platform, remain offline.
In an update shared on August 21, Colt said that while impacted business support systems are separate from customer infrastructure, its investigation found that some data has been taken by the attackers.
“We are now aware that the threat actor has accessed certain files that may contain data related to our customers,” Colt said, noting that cybercriminals posted titles of stolen documents on the dark web.
WarLock, a ransomware group that appears to have emerged in June, has taken credit for the attack on Colt on its Tor-based leak website.
The hackers claim to have stolen one million documents and are in the process of auctioning the files.
Colt is not the only telecom firm that has been named by WarLock on its leak website in recent days. The cybercriminals claim to have also stolen data from France-based Orange.
Orange Belgium and its parent company Orange recently disclosed separate cyber incidents, but it’s unclear if the WarLock claims are related to either of them.
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