On Saturday 21 June 2025 at 20:19 UTC, a CLDAP reflection targeted a airline booking customer in the Nordics. The attack peaked at 82.3 Gbps and lasted 52 minutes. Traffic originated from 4148 autonomous systems in 26 countries, predominantly compromised cloud VMs.
| Vector | CLDAP reflection |
| Peak | 82.3 Gbps |
| Duration | 52 min |
| Time to mitigation | 0.902 s |
| Attack traffic reaching origin | 0.077% |
| Legitimate traffic challenged | 0.55% |
Timeline
The attack was preceded by a publicly announced sales event. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 36 points of presence.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Keep origin IPs out of public DNS history.
- Review allow-listed partner ranges quarterly.
- Lower challenge thresholds on authentication endpoints during high-risk events.