Colt Technology Services Hit by WarLock Ransomware, Data Offered for Sale
UK-based telecommunications provider Colt Technology Services experienced a cyberattack starting around August 12, 2025, which disrupted support and online platforms. The WarLock ransomware group claimed responsibility, asserting they are selling one million documents containing sensitive financial, employee, and customer information for $200,000. The attack likely exploited a critical Microsoft SharePoint vulnerability (CVE-2025-53770). Stolen data reportedly includes employee salary data, customer contracts, and network architecture designs.
Signal context
First seen: Aug 12, 2025
Last updated: Jun 26, 2026
Status: Public signal
Key points
- Cyberattack began on or around August 12, 2025.
- WarLock ransomware group claimed responsibility.
- One million documents with sensitive financial, employee, and customer information offered for sale.
Signal analysis
BetaThis analysis groups the signal by industry, likely incident action and impacted security area. It helps compare this signal with other published signals without treating the labels as final determinations.
Sector: Information
Likely country: 🇬🇧 GB
inferred from signal text
The feed marks multiple actor roles. Treat this as a review signal rather than a final attribution.
- Source type: outside the affected organization
- Source type: possible insider or internal misuse
Impact area: Confidentiality, Availability
Likely asset: User or customer data
- 26 signals in the same sector
- 100 signals with the same likely impact area
- 1 signal linked to this organization/domain
External sources
Colt Technology Services Attack Claimed by Warlock Ransomware, Data Up for Salehttps://rhisac.org/threat-intelligence/colt-technology-services-attack-claimed-by-warlock-ransomware-data-up-for-sale/Public source from rhisac.org.
Warlock Colt Leak Analyzed: Sensitive Files Exposed - KELA Cyber Threat Intelligencehttps://www.kelacyber.com/blog/warlocks-attack-on-colt-leak-analyzed-sensitive-files-potentially-exposed/Public source from kelacyber.com.
WarLock Ransomware Attack on Colt Technology Services - Reliance Cyberhttps://www.reliancecyber.com/blog/warlock-ransomware-attack-colt-technology-services/Public source from reliancecyber.com.
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