University of Copenhagen data breach: hackers access test environment exposing 525,000 people's data
Severity: medium · Patch status: no-fix-needed · Since 2026-10-26
The University of Copenhagen confirmed a cyber attack in which hackers gained access to one of its test environments containing personal data of 525,000 people. Detected last Tuesday and disclosed Friday, the university later added 20,000 staff and students whose PIN/access codes were exposed. Exposed data includes full names, Danish national identity numbers (CPR), phone numbers, and email addresses, raising phishing and social engineering risks. The university restricted physical access to some campus locations while redistributing access codes, contained the attack, and blocked attacker access. No indication that systems supporting daily operations were accessed or disrupted. The incident was reported to the Danish Data Protection Agency and is being handled under GDPR. Investigation into full scope continues.
What to do
- Warn students and staff to be vigilant for phishing and independently verify unsolicited requests
- Rotate exposed PIN/access codes and review physical access controls
- Isolate and audit test environments holding production personal data; purge unnecessary PII
- Review logs for lateral movement from the compromised test environment into production systems
- Complete GDPR breach notification and regulator engagement
Sources
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