cti-bat.fr Listed by lockbit5 Ransomware Group: Ransomware Claim — What’s Alleged & What To Do
cti-bat.fr was listed today, 30 March 2026, by the lockbit5 ransomware group, which claims to have exfiltrated internal files. Individuals who have interacted with the organisation should check any communications they have received and review their accounts for unusual activity.
Breaking down the breach
The incident was reported on March 30, 2026. The only confirmed detail is that internal files were allegedly exfiltrated during a ransomware attack. No information has been released on the number of records involved, the timeline of the intrusion, or the method used to gain access. The scale of the operation and any ransom demands remain undisclosed.
The group behind it: lockbit5
Lockbit5 is a ransomware operation that follows the double-extortion model common among contemporary groups: data is encrypted on victim systems and copies are taken for later release. The group maintains a leak site where it lists organisations it claims to have compromised. In this case the site lists cti-bat.fr; the listing constitutes the group’s claim and has not been independently verified in public reporting. Lockbit5 has previously targeted organisations across multiple sectors and countries, publishing files when negotiations fail.
About cti-bat.fr
CTI BAT is a building company that operates in the construction sector. Companies of this type routinely maintain records on employees, subcontractors, suppliers, project specifications, and client contracts. A breach at such an organisation can therefore touch both corporate operational data and personal information belonging to individuals who have worked with or for the firm.
The information in question
The only data category stated is “internal files exfiltrated in ransomware attack.” No further breakdown—such as customer records, financial documents, or employee identifiers—has been published. Organisations in the construction industry commonly store personal details, contract information, and technical drawings; however, whether any of these categories are present in the exfiltrated material is unconfirmed.
What's at stake
Exposed internal files can contain details that enable targeted fraud, impersonation, or further attacks on the same individuals or partner organisations. For the company, the incident adds operational disruption and the possibility of regulatory scrutiny once the full scope is understood. Because the number of people affected is unknown, the breadth of personal risk cannot yet be quantified.
If your data was in this claimed breach
Individuals who have worked with or for cti-bat.fr should monitor their financial and email accounts for unusual activity and consider changing passwords on any services linked to the company. Enabling multi-factor authentication where available reduces the chance that exposed credentials can be reused. Readers can also run a free exposure scan of their email address against known breach data to check whether their information appears in public listings from this or other incidents.
AICompiled with AI assistance from public sources and published under our editorial standards.
How this breach connects
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Publicly posted by lockbit5 — unverified claim, pending independent verification
Breach listings — particularly those originating from ransomware or leak sites — are third-party claims that may be unverified, incomplete, or inaccurate. A listing does not by itself confirm that a breach occurred or that any specific data was exposed. Severity is an automated assessment, not a definitive rating. Verification status is shown where available.
Attributions to threat groups and methods reflect public reporting and, in some cases, unverified claims made by the groups themselves; they may be incomplete or later revised. Recent Breaches and GalaxyWarden are independent and are not affiliated with, and do not endorse, any company or group named on this page. This information is aggregated from public sources for awareness only and is not legal, security, or investment advice.