cmc.com.br Listed by lockbit5 Ransomware Group: Ransomware Claim — What’s Alleged & What To Do
cmc.com.br has been listed by the lockbit5 ransomware group, with internal files reported to have been exfiltrated. The breach was disclosed on 26 December 2025; an undisclosed number of individuals may be affected—review any official advisories and change passwords or enable multi-factor authentication if advised.
What happened
The only confirmed detail is the December 26, 2025 listing by LockBit5. The group asserts that internal files were taken during a ransomware operation against cmc.com.br. No independent confirmation of the exfiltration, the volume of data, or whether encryption occurred has been made public. The number of people affected is listed as unknown.
Inside lockbit5
LockBit is a ransomware-as-a-service operation that has been active for several years. It supplies encryption tools to affiliate attackers in exchange for a share of ransom payments. The group commonly uses a double-extortion approach: it encrypts systems and also claims to have copied data, then posts victim names on a leak site to pressure organizations into paying. Listings on the site represent the group’s own statements rather than verified events.
Who is cmc.com.br?
cmc.com.br is the domain of Colégio Miguel de Cervantes, an educational institution operating in Brazil. Schools of this type maintain records on current and former students, parents or guardians, and staff. These records typically include contact details, academic information, and administrative documents required for enrollment and operations.
What was likely exposed
The listing states that internal files were exfiltrated. No further description of file contents or categories has been provided. Organizations in the education sector routinely store personal identifiers, enrollment data, and communications, yet the precise nature of the material claimed in this case remains undisclosed.
Why it matters
Even without Reported Details, the presence of a school’s internal files on a ransomware leak site raises the possibility that personal information held for educational purposes could circulate. Such data can be used for targeted fraud or identity misuse over time. For the institution, the incident adds to operational costs associated with investigation, notification, and security improvements.
Were you affected?
Individuals connected to Colégio Miguel de Cervantes should monitor official communications from the school for any updates. A practical first step is to review account statements and credit reports for unusual activity. Readers can also run a free exposure scan of their email address against known breach data sets to check whether their information has appeared in previously published collections.
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.