L S GRIM Listed by sinobi Ransomware Group: Ransomware Claim — What’s Alleged & What To Do
L S GRIM has been listed by the sinobi ransomware group, with internal files reported exfiltrated in an attack disclosed on 18 December 2025. An undisclosed number of people may be affected; anyone connected to the organisation should verify whether their information was exposed and take protective steps.
Breaking down the breach
The only confirmed information is the listing itself and the assertion that files were removed during a ransomware operation. No date of the intrusion, volume of data, or method of access has been disclosed. The organization has not issued a statement confirming or denying the claims, and the total number of people affected remains unknown.
Inside sinobi
Sinobi is a ransomware group that maintains a public leak site where it lists organizations it claims to have targeted. Such groups typically gain initial access through phishing, stolen credentials, or unpatched systems, then move laterally to locate and copy data before deploying encryption. Their listings serve as pressure on victims during ransom negotiations. The group’s claim regarding L S GRIM has not been independently verified beyond the site posting.
Who is L S GRIM?
L S GRIM, also referred to as L.S. Grim Consulting Engineers, is a Mid-Atlantic engineering firm that provides mechanical, electrical, and plumbing design services along with fire-protection and project-management support. The company works with clients that require code-compliant systems and LEED-oriented solutions, and it has operated for more than thirty years. Organizations in this sector routinely receive and generate detailed technical documents for building projects.
What was likely exposed
The listing states only that internal files were exfiltrated. The precise categories of information have not been released. Engineering consultancies of this type commonly store project drawings, equipment specifications, client correspondence, and facilities-management records. Without an official disclosure, the exact contents of the claimed exfiltration cannot be confirmed.
Why it matters
Engineering files can contain site-specific details about building systems, security measures, and operational procedures. If such material reaches unauthorized parties, it may be used to identify physical or digital vulnerabilities in client facilities. For the firm, the incident adds operational disruption and potential loss of client trust even if the full scale of exposure stays limited.
If your data was in this claimed breach
Monitor accounts associated with any projects or services linked to the firm for unusual activity. Enable multi-factor authentication on professional and personal accounts, and review any recent password resets or login alerts. Individuals can also run a free exposure scan of their email address against known breach data to check for appearances in public listings.
AICompiled with AI assistance from public sources and published under our editorial standards.
How this breach connects
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Publicly posted by sinobi — 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.