Colt Know-how faces multi-day outage after WarLock ransomware assault
August 17, 2025 
WarLock ransomware hit Colt Telecom, inflicting outages in internet hosting, porting, Colt On-line, and Voice API since August 12.
UK-based Colt Know-how Providers suffered a cyberattack, reportedly brought on by WarLock ransomware, leading to multi-day outages for internet hosting, porting, Colt On-line, and Voice API companies.
Colt, formally generally known as Colt Know-how Providers Group Restricted, is a multinational telecommunications firm headquartered in London, United Kingdom. It was based in 1992 as Metropolis Of London Telecommunications and initially centered on constructing a telecoms community in London. Over time, Colt expanded its operations throughout Europe, Asia, and North America.
The compant makes a speciality of offering high-performance connectivity and communication options for companies. Its companies embrace information, voice, cloud, and managed IT companies, with a deal with delivering scalable, safe, and dependable community infrastructure. Colt owns and operates a big fiber-optic community connecting 1000’s of buildings throughout a number of cities and nations by way of metropolitan and long-haul networks.
The agency serves a variety of enterprise purchasers, from massive multinational firms to smaller enterprises, and operates in over 40 nations with greater than 6,000 workers. Colt is thought for its robust dedication to customer support, innovation, and sustainability.
Menace actors put stolen information up on the market. The incident started on August 12, and disruptions persist as the corporate’s IT groups work nonstop to comprise the influence and restore affected techniques.
Colt initially described the disruption as a “technical problem” however later confirmed it was a cyberattack. The agency shut down techniques to mitigate the menace. The corporate identified that Core community infrastructure was not impacted. The corporate has notified authorities however shared no technical particulars on the assault, and there’s nonetheless no timeline for restoring operations.
The favored cybersecurity professional Kevin Beaumont believes that menace actors doubtless breached sharehelp.colt.internet through Microsoft SharePoint flaw CVE-2025-53770, then remained inside its community for over every week. The researcher additionally speculates that Colt is attempting to cowl it up.
A WarLock affiliate, “cnkjasdfgd,” claimed the assault, providing 1M stolen documents for $200K, together with monetary, worker, buyer, and inside information.
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(SecurityAffairs – hacking, WarLock ransomware)
