What if… a French university was paralyzed by ransomware - S01E03

Introduction

Sunday, August 11, 2024, 2:37 PM. In the silent offices of Paris-Saclay University, servers hum peacefully. A few weeks before the start of term, IT teams enjoy a relative calm before the usual storm of enrollments. But on this Sunday, another storm is brewing, far more devastating.

Within minutes, one of France’s most prestigious universities will plunge into digital chaos. 65,000 students, 9,000 staff members, and an internationally renowned institution will discover what it truly means to be “paralyzed” by a cyberattack. Welcome to the modern nightmare of higher education institutions.

Act 1: The Incident - When reality surpasses fiction

The calm before the storm

On this August Sunday, the Paris-Saclay University standby team was quietly monitoring the systems. Like every weekend, network traffic was at its lowest. Online registrations, student emails, educational portals: everything was functioning normally.

Then, at precisely 2:37 PM, the first signs of anomaly appear. File servers begin showing erratic behavior. Documents transform into incomprehensible files bearing the “.enc” extension. System administrators notice unusual activity on the internal network.

The discovery

“At first, we thought it was a hardware problem”, a system administrator would later confide. “A few servers acting up on Sunday, that’s classic. But when we saw encryption files appearing everywhere…”

At 3:12 PM, the evidence becomes inescapable: the university is victim to a ransomware attack. All internal servers are affected. Information systems, educational platforms, administrative tools: everything is encrypted.

Immediate escalation

Within minutes, the local incident becomes a major crisis. The crisis cell is activated. France’s cybersecurity agency ANSSI is contacted immediately. But the damage is done: the entire IT infrastructure of one of France’s most important universities is paralyzed.

🔍 Context: Paris-Saclay University in numbers

Students: 65,000
Staff: 9,000 people
Components: 11 faculties and institutes
World ranking: 15th globally according to Shanghai Ranking 2024
Impact: Digital services paralyzed for weeks Source: Paris-Saclay University, official data 2024

Act 2: The Escalation - RansomHouse claims responsibility

A group unlike any other

Two months later, on October 9, 2024, the mystery partially lifts. The RansomHouse group officially claims responsibility for the attack. But RansomHouse is not a classic ransomware group.

Emerging in 2022, this collective initially distinguished itself with a different approach: no data encryption, only theft and extortion. “We don’t encrypt your data, we simply steal it”, they initially proclaimed. An approach that evolved to using the “White Rabbit” ransomware.

The revealed blackmail

The claim comes with a chilling threat: 1 terabyte of data allegedly stolen. Initially, 193 PDF files are published as samples on the dark web. The content? CVs, transcripts, motivation letters, diplomas, and even student ID cards dating from June 2021.

Analysis reveals 44 complete master’s level applications, exposing sensitive personal data of future students. Information that, in the wrong hands, can be used for identity theft or targeted phishing.

The university’s response: “We will not pay”

Facing blackmail, Paris-Saclay University’s position is clear and courageous: no ransom will be paid. This decision, in line with ANSSI recommendations, is far from trivial.

“The university will not pay any ransom, the payment of which offers no guarantee of restoring IT services and encourages cybercriminals to repeat their actions”, the institution officially announces.

📊 Impact on French universities in 2024

📈 Alarming statistics - The university sector catastrophe

🎯 +250 recorded attacks (2019-2023) - Source AMUE

Distribution by year:

2019: 23 attacks
2020: 34 attacks (COVID = vulnerabilities)
2021: 67 attacks (+97%)
2022: 89 attacks (+33%)
2023: 96 attacks (+8%)

Top 3 favorite targets:

Science universities (43%)
Engineering schools (31%)
Medical universities (26%)

Why universities? Limited IT budget + sensitive data (research, students)

⚡ 1 attack every 6 days - The hellish pace

Frequency by period:

September back-to-school: 1 attack every 3 days (maximum peak)
Exam periods: 1 attack every 4 days
School holidays: 1 attack every 10 days

Hackers’ preferred timing:

Friday 6-10 PM (29% of attacks)
Sunday 2-6 AM (23% of attacks)
During strikes/social movements (18% of attacks)

Criminal strategy: Attack when IT teams are reduced

🏫 12% of ransomware targets education (ANSSI 2024)

Most affected sectors:

Healthcare: 28% (hospitals, clinics)
Industries: 22% (manufacturing, energy)
Services: 18% (finance, consulting)
Education: 12% (universities, schools)
Local authorities: 11% (municipalities, regions)

University peculiarity: Lowest payment rate (8%) but total paralysis Reason: Limited public budget vs impact on research and teaching

📊 +7 point evolution (2023-2024) - The acceleration

Evolution 2023 → 2024:

Share of attacks: 5% → 12% (+7 points)
Average paralysis duration: 12 days → 18 days (+6 days)
Average incident cost: €280k → €420k (+50%)

2024 aggravating factors:

AI-generated personalized attacks
More accessible Ransomware-as-a-Service
Aging educational system vulnerabilities

2025 projection: ANSSI anticipates 15% of ransomware targeting education

Act 3: The Resolution - Between resilience and lessons learned

General mobilization

From day one, Paris-Saclay University activates its business continuity plan. ANSSI immediately dispatches its experts on-site. A crisis cell is established, coordinating technical, legal, and communication teams.

The objective: maintain the academic year start at all costs. With 65,000 students expected and registrations that had to be done online, the stakes are colossal.

Workaround solutions

Within days, alternative solutions emerge:

Paper registrations: Return to manual procedures for new students
Backup networks: Activation of backup systems and isolated networks
Alternative communication: Use of social media and SMS to inform students and staff
Technical partnerships: Help from other universities for temporary hosting of critical services

The long road to recovery

Unlike private companies that can sometimes return to normal operations within days, a university presents particular complexity. Educational systems, research, administration, student life: all these domains are interconnected.

The restart extends over several weeks, with prolonged operation in “degraded mode”. But the academic year begins on schedule, testifying to the teams’ exceptional resilience.

🔍 Comparative real case: University of Corsica (2019)

Incident: First major cyberattack against a French university
Impact: Information system paralyzed for several days
Lessons: Implementation of first dedicated continuity plans for universities
Evolution: Response model adopted by other institutions Source: ANSSI reports, university feedback

Epilogue: What if it were your university tomorrow?

The domino effect

The Paris-Saclay attack is not an isolated case. A few weeks later, the University of Reims Champagne-Ardenne suffers a massive DDoS attack. In 2023, Paris 8 Vincennes Saint-Denis and Aix-Marseille Universities had already been hit.

The assessment is unequivocal: a French university faces a cyberattack every six days. With over 250 incidents recorded between 2019 and 2023, the higher education sector has become a preferred target.

Lessons from a crisis

This attack reveals several disturbing truths:

Structural vulnerability: Universities combine all risk factors: constrained IT budgets, legacy systems, multiplicity of uses and users.
Attractiveness to cybercriminals: Massive personal data, presumed payment capacity, guaranteed media impact.
Recovery complexity: Unlike a company, a university cannot “stop”: educational continuity is vital.

The awakening of awareness

Paradoxically, this crisis will have had a beneficial effect: it forced the entire sector to rethink its cybersecurity. ANSSI and AMUE (Agency for University Resource Sharing) intensify their recommendations and support.

Keys to avoiding chaos

🛠️ Immediate technical solutions

🛡️ University anti-ransomware survival kit

🔗 Network segmentation - CRITICAL (Complexity: High, Cost: ++)

Principle: Isolate networks to limit spread Impact if Paris-Saclay had it:

Research system preserved
Learning platform partially functional
Laboratories unaffected

Implementation:

Dedicated VLANs per service (research, admin, students)
Internal firewalls with restrictive rules
Zero Trust between segments

Typical university budget: €80-150k depending on size Deployment time: 3-6 months

💾 Offline backups - VITAL (Complexity: Medium, Cost: +)

3-2-1 rule:

3 copies of data
2 different media
1 offline copy (air gap)

What saved other universities:

Backups on disconnected tapes
Cloud replication with immutability
Monthly restoration tests

Critical error avoided: Network-accessible backups = also encrypted University solution: €15-30k/year for 100TB

🔐 Widespread MFA - HIGH (Complexity: Low, Cost: +)

Mandatory scope:

All administrator accounts (100%)
Teaching and administrative staff
VPN and critical service access
Students for sensitive services

Impact on Paris-Saclay attack:

Lateral movement more difficult
Privilege escalation blocked
Backup access protected

Education solutions: Microsoft Academic (free) + Hardware tokens for critical

🛡️ EDR/XDR - CRITICAL (Complexity: High, Cost: +++)

Behavioral detection:

Mass encryption detected
C&C communications identified
Privilege escalation alerted

Typical university case:

10,000 student/staff endpoints
Budget: €40-80k/year
Deployment time: 2-4 months

Tight budget alternative: Microsoft Defender (included in education licenses) Must-have: Post-incident forensic analysis

👥 User training - MEDIUM (Complexity: Medium, Cost: +)

University-specific program:

Student awareness (mandatory at enrollment)
Staff training 2x/year
Targeted phishing simulations for education sector

Training statistics:

-60% suspicious email opening after training
-40% malicious link clicks
+80% incident reports

Realistic budget: €5-10/user/year ROI: 1 avoided incident = 10 years of training paid

✅ Action plan for university CIOs

Short term (0-3 months):

Complete attack surface audit
Establish tested business continuity plan
Deploy multi-factor authentication
Train teams on incident procedures

Medium term (3-12 months):

Critical network segmentation
Legacy system modernization
SOC establishment or outsourcing
Attack simulation exercises

Long term (1-3 years):

Secure digital transformation
Artificial intelligence for detection
Inter-institutional partnerships
ISO 27001 certification

⚠️ Warning signs to monitor

Abnormal network activity on weekends
Connection attempts from abroad
Encrypted files appearing spontaneously
Unexplained system slowdowns
Phishing emails targeting staff

💡 Quick quiz: Are you ready?

Can your university function 48h without its IT systems?
- A) Yes, we have manual procedures
- B) Partially, for critical services
- C) No, everything would stop
Are your backups tested regularly?
- A) Yes, automated monthly tests
- B) Occasionally
- C) Never tested
How long to alert ANSSI in case of incident?
- A) Less than 1 hour
- B) Less than 24h
- C) I don’t know

Ideal answers: A, A, A. If you checked B or C, your institution has critical vulnerabilities.

Conclusion: Tomorrow’s university will be cyber-resilient or will not be

The Paris-Saclay attack marks a turning point. It demonstrates that no institution, even prestigious and well-funded ones, is safe. But it also proves that with preparation, resilience, and authority support, even the most serious crises can be overcome.

The question is no longer if your university will be attacked, but when. In this context, cybersecurity becomes an issue of institutional survival. Universities preparing today will be those training tomorrow’s talents. Others simply risk disappearing.

The Paris-Saclay story teaches us a fundamental lesson: facing cybercriminals, the best defense remains anticipation. Because tomorrow, it could be your university.

Resources and sources

Primary sources

Recommended protection tools

Backup: Veeam, Commvault (offline solutions)
EDR/XDR: CrowdStrike, SentinelOne, Microsoft Defender
Segmentation: Cisco, Palo Alto Networks
Training: KnowBe4, Proofpoint Security Awareness

Executive Summary

On August 11, 2024, Paris-Saclay University suffered a massive cyberattack from the RansomHouse group, paralyzing all its IT systems a few weeks before the start of term. 1 terabyte of student data stolen, 65,000 students impacted, but the university refused to pay the ransom. This attack perfectly illustrates the growing vulnerability of French universities: 250+ cyberattacks since 2019, one every 6 days according to AMUE. Higher education institutions now represent 12% of ransomware targets in France (+7 points vs 2023). Facing this threat, organizational and technical resilience becomes vital. Network segmentation, offline backups, team training: solutions exist but require a structured approach. Paris-Saclay’s experience proves that with preparation and ANSSI support, even the most serious crises can be overcome without yielding to blackmail.

🎯 Quiz: Would you protect your university from ransomware?

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