A ransomware group calling itself SilentRansomGroup claims to have obtained data from law firm Katten Muchin Rosenman, according to a listing posted on the group’s dark web leak site on September 3, 2026. This claim has not been independently verified and comes from the group’s own leak-site posting, which is tracked by ransomware.live, a security research platform that monitors ransomware groups’ public leak sites. Katten Muchin Rosenman has not issued any public statement confirming or denying the claim.
What we know — and don’t
- A group identifying itself as SilentRansomGroup listed Katten Muchin Rosenman on its leak site with a claimed date of September 3, 2026.
- Katten Muchin Rosenman operates in the legal sector, providing legal services to corporate and individual clients.
- The specific types of data the group claims to have accessed have not been disclosed by the group and have not been confirmed by the company or any regulator.
- No official confirmation of a breach, its scope, or its impact has been made public at this time.
What should you do if you have an account with this company?
- Change your password for any account associated with this firm, and avoid reusing that password elsewhere.
- Enable two-factor authentication (2FA) wherever it is offered, particularly on email and financial accounts.
- Be alert for phishing emails, texts, or calls that reference this firm or claim to relay urgent legal or security notices — attackers often exploit breach news to trick people into clicking malicious links.
- Monitor your financial and email accounts for unusual activity in the weeks following any such claim.
- Consider using an identity monitoring service like a service like Aura or LifeLock to help watch for signs that your personal information is being misused.
- Keep records of any suspicious communications in case they are needed later for reporting or verification purposes.
BreachLetter will update this page if Katten Muchin Rosenman confirms this incident, if new details emerge from the group’s leak site, or if the matter is officially reported to regulators.