Greek school-exam system DDoS attack
A massive multi-day DDoS attack on Greece's 'Subject Bank' (Trapeza Thematon) high-school exam platform disrupted nationwide exams with up to 280,000 connections per second and 165 million hits from 114 countries, the largest attack on a Greek public body.
- Victim
- Greek Ministry of Education (Subject Bank / Trapeza Thematon)
In late May 2023, Greece's nationwide high-school examination platform — the Subject Bank (in Greek, Trapeza Thematon), operated by the Ministry of Education — was hit by a sustained distributed denial-of-service (DDoS) attack during the live exam period. Officials called it the most significant cyberattack ever on a Greek public-sector organisation.
What happened
As students sat down to take their exams on 29 May 2023, the platform that distributes exam questions began to buckle under a flood of malicious traffic. The DDoS assault was both large-scale and long-lasting, peaking at up to 280,000 connections per second. Over the course of the incident the platform absorbed roughly 165 million hits originating from 114 countries — a clear sign of a globally-distributed botnet rather than a domestic prank.
Crucially, this was a volumetric availability attack, not a data breach. Officials from the Ministries of Education and Digital Governance stressed that the attackers did not gain access to the system's components or to exam data; the platform was overwhelmed and made temporarily unavailable, but not penetrated.
Impact
- Exam starts were delayed across the country, with students left waiting in classrooms for hours over consecutive days.
- Some exams had to be rescheduled or rerun, causing stress and disruption for tens of thousands of students and teachers.
- The incident became a political flashpoint, with sharp exchanges between government and opposition over national cyber-resilience.
- No exam content or personal data was reported stolen.
Response
Greece's Supreme Court Public Prosecutor, Isidoros Dogiakos, ordered a judicial investigation with the assistance of the Hellenic Police's Cyber Crime Unit. The government emphasised that defences had ultimately held — the system was restored and exams completed — and that the attack's scale and sophistication pointed to a well-resourced actor, though no public attribution was confirmed and no ransom was demanded.
Why it matters
The Subject Bank attack is a landmark national availability case. It showed how a DDoS — often dismissed as a blunt instrument — can inflict outsized real-world harm when aimed at a time-critical public service with no tolerance for downtime, such as national exams affecting an entire student cohort. The incident pushed Greece to harden the resilience and DDoS mitigation of critical e-government platforms and underscored that defending education infrastructure is now a matter of national importance, not just IT housekeeping.
Timeline
As Greek high-school exams begin, the Subject Bank (Trapeza Thematon) platform comes under a large-scale DDoS attack, delaying exam starts nationwide.
The attack continues into a second day; the platform peaks at up to 280,000 connections per second and receives 165 million hits from 114 countries.
The Ministries of Education and Digital Governance call it the most significant attack ever on a Greek public government organisation.
Supreme Court prosecutor Isidoros Dogiakos orders a judicial investigation, assisted by the police Cyber Crime Unit.
Officials stress the DDoS did not breach the system or access exam data; the platform was overwhelmed, not penetrated.
Sources
- therecord.mediahttps://therecord.media/cyberattack-disrupts-greek-exams
- balkaninsight.comhttps://balkaninsight.com/2023/05/31/greece-prosecutor-calls-a-probe-into-a-school-exam-cyber-attack/
- greekcitytimes.comhttps://greekcitytimes.com/2023/05/31/greeces-education-ministry-faces-unprecedented-cyber-attack-targeting-high-school-exam-platform/
- dig.watchhttps://dig.watch/updates/greek-prosecutor-orders-investigation-into-school-exam-cyberattack