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Medium

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.

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.

Connected intelligence

Signal brief

Follow the organization, likely method and potential impact to explore connected Shadow Tier intelligence.

02

Likely method

Ransomware

Malware, Hacking activity

03

Potential impact

Data Exposure

Confidentiality, Availability

Published
Aug 12, 2025
Updated
Jun 26, 2026
Confidence
Medium
Evidence
3 sources

Structured assessment

Signal analysis

This 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.

Threat source

Malware, Hacking activity

Watch ransomware, endpoint compromise and business interruption exposure.

  • Source type: possible insider or internal misuse

Business impact

Potential operational disruption
Impact area
Confidentiality, Availability
Likely asset
User or customer data

Mentioned entities

ColtData DisclosureColt Technology Services HitWarLock RansomwareColt Technology ServicesThe WarLockMicrosoft SharePointCVE-2025-53770StolenCyberattack

Quick context

Questions about this signal

What happened in this signal?

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.

When was this signal reported?

Shadow Tier lists Aug 12, 2025 as the signal date.

Which organization is connected to this signal?

Colt is the organization connected to this public signal.

Explore Colt
Which attack pattern is relevant?

This signal is connected to current ransomware incidents based on its reported incident context.

Explore current ransomware incidents
Which impact area is relevant?

This signal is connected to data exposure and breach intelligence based on its reported consequences.

Explore data exposure and breach intelligence