Thialf
About the organisation
***.nl zoominfo.com/c/thialf/430686423 Thialf is a world-renowned ice arena located in Heerenveen, Netherlands, often referred to as the "Cathedral of Speed Skating." It serves as the home base for the Dutch national speed skating team and hosts a wide range of ice sports, including long track and short track speed skating, figure skating, and ice hockey. Recently, it was officially confirmed as the long-track speed skating venue for the 2030 Winter Olympics. The facility is celebrated for its modern, sustainable design and its role as a major hub for both elite professional competitions and public recreational skating.
What the listing means
Thialf appeared on the thegentlemen leak site on 23 July 2026. Groups publish a victim once negotiations stall or as pressure during them, so a listing usually means data was already exfiltrated. This group has published 134 claims in the last 30 days and remains active.
Recommended actions
- Treat any unsolicited message referencing Thialf as suspicious — leaked data gets weaponised for phishing within days.
- If you hold an account on thialf.nl, change that password now, update it anywhere you reused it, and enable two-factor authentication.
- Other Energy & Utilities organisations should review this group's known TTPs and validate detection coverage against them.
- Watch for follow-on extortion: stolen data is often re-leaked or resold after the initial listing.
- A leak-site listing is a claim made by the attacker, not a confirmed breach — check the organisation's own disclosures before acting on it.
Leak-site evidence
Listing URL https://www.ransomware.live/id/VGhpYWxmQHRoZWdlbnRsZW1lbg==