mostykatowice.pl Listed by lockbit5 Ransomware Group: Ransomware Claim — What’s Alleged & What To Do

mostykatowice.pl, the online presence of Spółka Mosty Katowice, was listed on December 26, 2025 by the ransomware group lockbit5. The listing states that internal files were exfiltrated during a ransomware attack. No figure for the number of people affected has been released, and the company has not confirmed the incident or provided further details.

Breaking down the breach

The only confirmed information is the listing itself and the group’s assertion that internal files were taken. No date of the intrusion, volume of data, or method of access has been disclosed. It remains unknown whether the files were encrypted, whether any ransom was demanded or paid, or whether the data has been published.

Who is lockbit5?

Lockbit5 is a ransomware operation that has conducted numerous attacks on organisations worldwide. The group typically uses encryption to disrupt operations and threatens to publish stolen data if a ransom is not paid. Its listings on a dedicated leak site constitute a claim by the group; independent verification of the underlying breach is required in each case.

mostykatowice.pl and its sector

Spółka Mosty Katowice operates in the engineering and design sector in Poland, where it is described as one of the market leaders. Companies in this field routinely handle project documentation, technical specifications, client correspondence and internal operational records. A breach at such an organisation can therefore involve material that extends beyond the company itself to its clients and partners.

What was likely exposed

The listing refers only to “internal files.” The precise categories of data have not been published. Organisations of this type commonly store engineering drawings, contract documents, employee records and communications with public-sector or private clients, but the exact contents of any exfiltrated material remain unconfirmed.

What's at stake

Exposure of internal engineering and commercial files can create operational, contractual and regulatory consequences for the company and any third parties named in the documents. Individuals whose personal data appears in those files may face risks of identity misuse or targeted fraud, though the presence of such data has not been established.

Were you affected?

Individuals who have had professional contact with mostykatowice.pl or its projects should monitor their email and financial accounts for unusual activity. Checking whether an email address appears in known public breach datasets provides one practical starting point; several free online services allow users to run such a scan without submitting additional personal information.

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