Gauthier Tissus: 54 GB of internal data published after a cyberattack

On 17 April 2026, Gauthier Tissus — a French textile manufacturer specializing in the weaving and finishing (ennobling) of technical, multi-risk and brand-image fabrics, based in the Rhône-Alpes region — was named on the leak site of the Lamashtu extortion group. The attackers claimed to have exfiltrated internal data and threatened to publish it as leverage against the company.

The leak is reported to total roughly 54 GB, comprising about 8,500 files dated between 1996 and 2026, including recent backups from December 2025 and January 2026. This is a data-theft extortion operation; Lamashtu, which surfaced in April 2026, has not been confirmed to deploy file-encrypting ransomware as opposed to pure data theft and publication.

The exposed material reportedly spans:

• Financial records (Sage 100 backups, invoices, treasury data)
• Human resources data (employment contracts, evaluations)
• Commercial information (client files, orders, shipments)
• Intellectual property (manufacturing processes and R&D)
• Technical system exports (SQL databases, system archives)
• Email archives (PST format)

As of disclosure, the incident remained ongoing: the data had been advertised on the threat actor's leak site, and the company had not issued a public confirmation. The breach was tracked by multiple threat-intelligence sources, including Ransomware.live and BreachSense.