Brinztech Alert: “ByteToBreach” Leaks Eurofiber Client List, Exposing French Gov, Airbus, Thales

Dark Web News Analysis

A threat actor, “ByteToBreach,” has provided a partial list of the 3,600+ clients impacted by the Eurofiber data breach. This claim, if true, represents one of the most severe supply chain attacks in European history, compromising the “crown jewels” of national critical infrastructure.

My analysis confirms Eurofiber is a “vital” infrastructure provider operating over 76,000 km of fiber network and 11 data centers. The victim list is a “who’s-who” of the French and European economy, including:

• Government & Defense: Airbus, Thales, French Ministry of Interior, Ministry of Sustainable Development, French National Railway (SNCF).
• Critical Infrastructure (Telecom & Energy): Orange Telecom, SFR Telecom, Engie, TotalEnergies, Suez, Colt Technology.
• Finance & Insurance: AXA Group, BPCE Group (a major French bank), Banque Misr.
• Global Consulting & IT: Accenture, CGI Group.
• Healthcare: Sanofi, multiple hospitals.
• Retail: Decathlon, Auchan Group, Fnac, Boulanger.

The attacker is not selling a simple PII list. They are selling the entire GLPI (IT Asset Management) database, which contains the operational core of Eurofiber’s clients. The leaked data allegedly includes:

• SSH Private Keys
• VPN Configurations
• Admin API & App Keys
• Source Code & SQL Backups
• Internal client support tickets and messages

The attacker claims they used a slow, time-based SQL injection on Eurofiber’s GLPI instance, which was an outdated, vulnerable version (likely 10.0.7-10.0.14). Public data confirms critical SQLi vulnerabilities (like CVE-2024-29889 and CVE-2025-24799) affect these versions. The attacker claims to have contacted Eurofiber and GLPI (Teclib) for ransom but was ignored, leading to this public sale.

Key Cybersecurity Insights

This alleged data breach presents a critical and immediate threat:

• Catastrophic Supply Chain Compromise: This is the primary threat. The breach of one provider (Eurofiber) is a direct, high-privilege compromise of 3,600+ clients, including top-tier government, defense, and financial entities.
• Deep Operational Data Exposure: The type of data (SSH keys, VPN configs, API keys) is the “crown jewels.” This allows attackers to bypass all perimeter defenses and gain trusted, administrative access to the victims’ core infrastructure.
• Vulnerability in Core Enterprise Software: The root cause is a simple, unpatched vulnerability in a core IT management tool (GLPI). This is a systemic failure, proving that internal-facing tools are as critical to secure as public-facing ones.
• Ineffective Ransom Negotiation: The attacker’s claim of being ignored has escalated the incident from a private extortion attempt to a public, global supply chain crisis, as this “goldmine” of data is now for sale to the highest bidder.

Mitigation Strategies

In response to this, all 3,600+ clients, especially those named, must assume a full compromise:

• Immediate Credential Rotation (TOP PRIORITY): All clients must immediately assume their SSH keys, API keys, and VPN configurations are compromised. They must rotate everything that could have been documented in a Eurofiber GLPI ticket.
• Trigger Third-Party Incident Response: This is a confirmed breach of a critical vendor. All clients must activate their third-party incident response plans, begin internal threat hunting for indicators of compromise, and monitor for any anomalous access using the leaked credentials.
• Patch GLPI & Remove from Public Internet: For all organizations, not just Eurofiber: audit all GLPI (and similar IT) instances. Patch them immediately (especially for SQLi CVEs) and, most importantly, remove them from the public internet. They should only be accessible via a VPN with MFA.
• Secure Data Handling in Tickets: A new policy is mandatory. NEVER put private keys, root passwords, or permanent API keys in a ticketing system (GLPI, Jira, etc.). Use a secure, time-bombed secrets vault (like HashiCorp Vault) and share a temporary link to the secret, not the secret itself.

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