high severity December 26, 2025 · 4 min read Unverified claim — what this is

mostykatowice.pl Listed by lockbit5 Ransomware Group

If you are a customer of mostykatowice.pl, here’s what is being claimed, and what it would mean for you.

Spółka Mosty Katowice to jeden z liderów rynku projektowego w Polsce. Na swój sukces pracujemy...
— from LockBit’s own leak-site posting. This is the group’s claim, quoted verbatim; it is not GalaxyWarden’s reporting and has not been independently verified.

mostykatowice.pl Listed by lockbit5 Ransomware Group

On December 26, 2025, the Polish engineering company Mosty Katowice appeared on the LockBit 5 ransomware leak site with internal files reportedly exfiltrated during an attack. The company, a leader in bridge and infrastructure design in Poland, had its data listed after failing to meet the group's demands, exposing potentially sensitive business and personal records to anyone who visits the dark-web portal.

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What Public Reporting Shows

Public reporting indicates that LockBit 5 published a post on its leak site containing samples of Mosty Katowice's internal documents. The listing states that attackers successfully exfiltrated files before encrypting systems or as part of their standard double-extortion process. No exact victim count has been released, and the precise volume or types of data remain unclear from the initial posting, though ransomware groups routinely include employee details, contracts, financial records, and correspondence in such leaks.

The incident follows the typical timeline seen in LockBit operations: initial access, data theft, encryption of victim systems where applicable, and public shaming when ransom is not paid. Available reporting describes the data as "internal files," consistent with the operational data Polish engineering firms maintain on public infrastructure projects, suppliers, and staff.

Why This Matters for You and Your Family

When a company like Mosty Katowice is breached, the information exposed often includes names, addresses, phone numbers, email accounts, and sometimes national identification numbers of employees, contractors, and their families. If your employer, your spouse's employer, or a company you have worked with appears in such leaks, your personal data can spread quickly across criminal marketplaces.

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What the free scan actually returns

Sample resultyou@email.comIllustrative — not a real person

Found on people-search siteswe remove these

These listings are live, public, and legal to remove — and removing them is what we do.

value redacted in this sampleage, relatives, address historySpokeo

value redacted in this samplephone, household, property recordsBeenVerified

value redacted in this sample580 companies checked

Found in breach recordsverifiedreported — unverified

Each record is labeled: confirmed breach data, or an attacker’s claim no one has verified.

verifiedvalue redacted in this samplepassword + phone · 2024telecom breach

unverifiedvalue redacted in this sampleclaimed in ransomware listing · 2026leak-site claim

Leaked data cannot be deleted from the internet — anyone claiming otherwise is lying. Broker listings can be removed. We do the second, and show you exactly what to fix from the first.

Report details & sourcing

Attributed to LockBit · 3412 incidents tracked →

Severity High the filing does not enumerate what was exposed

Disclosed December 26, 2025

Last reviewed August 8, 2026

Affected Unconfirmed

By GalaxyWarden Threat Research · Editorial & sourcing standards

Unverified claim — what this report is

This page documents a public listing on a ransomware/extortion group’s leak site, tracked via public threat-intelligence sources. A listing is the attacker’s claim. GalaxyWarden aggregates and reports such claims; we have not independently verified that a breach occurred, what data (if any) was taken, or the accuracy of anything the group asserts, and the named organisation has not necessarily confirmed the incident. Sections above describe what the listing shows and the group’s documented history — not verified findings about the named organisation. If you represent this organisation and believe anything here is inaccurate, tell us and we’ll review it promptly.

Editorial & sourcing policy

GalaxyWarden is a breach-monitoring service and news aggregator. We do not exfiltrate, host, purchase, or redistribute stolen data. Breach information is compiled from publicly accessible sources and threat-intelligence platforms, and is reported as claims attributed to their source. We promptly correct or remove material shown to be inaccurate — see our content & takedown policy or write to support@galaxywarden.com.

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LockBit — 3412 incidents tracked

Every breach we've attributed to LockBit, in one running log. See who else they've hit →

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