Communitymosaic.co.uk Listed by tengu Ransomware Group: Ransomware Claim — What’s Alleged & What To Do

On 4 March 2026 the ransomware group tengu listed Communitymosaic.co.uk on its leak site, stating that internal files had been taken from the organisation. No confirmation of the claim has been issued by the company, and the number of individuals whose data may be involved remains unknown. The listing follows a pattern seen across multiple sectors in which ransomware operators publish victim names to pressure targets into payment negotiations.

Breaking down the breach

The only public record of the incident is the listing itself. It describes the removal of internal files during a ransomware operation but supplies no further technical detail on how access was obtained, the volume of data involved, or the date of the intrusion. Community Mosaic CIC has not published a statement confirming or denying the claims.

Who is tengu?

Tengu is a ransomware operator that maintains a public leak site to list organisations it claims to have compromised. Groups of this type typically encrypt systems, exfiltrate data, and then threaten to publish the material unless a ransom is paid. Their listings are presented as evidence of successful operations, though independent verification of each claim is often unavailable at the time of publication.

Who is Communitymosaic.co.uk?

Community Mosaic CIC is a community interest company incorporated on 21 June 2018 and registered in Peterborough, Cambridgeshire. Organisations of this legal form are established to pursue social or community objectives rather than private profit. They routinely collect and store records relating to service users, staff, volunteers, and local partners.

The information in question

The listing refers only to “internal files exfiltrated in ransomware attack.” No inventory of specific data categories has been released. Community interest companies commonly hold contact details, membership or service records, and administrative correspondence, yet the precise contents of any exfiltrated material remain unconfirmed.

Why it matters

Even without Reported Details, the exposure of internal files can create follow-on risks for individuals whose information appears in operational records. For the organisation, the incident adds pressure to demonstrate that appropriate security measures were in place and that any affected parties will be notified in line with regulatory requirements.

Were you affected?

Individuals connected to Community Mosaic CIC should monitor official communications from the company for any formal notification. Practical steps include:

• Reviewing bank and email accounts for unusual activity
• Changing passwords for any services linked to the organisation
• Running a free exposure scan of your email address against known breach data

AICompiled with AI assistance from public sources and published under our editorial standards.