On Saturday 22 August 2026 at 00:17 UTC, a TLS handshake exhaustion targeted a municipal services customer in Iberia. The attack peaked at 483.1 million requests per second and lasted 124 minutes. Traffic originated from 3160 autonomous systems in 90 countries, predominantly residential proxy networks.
| Vector | TLS handshake exhaustion |
| Peak | 483.1 million requests per second |
| Duration | 124 min |
| Time to mitigation | 0.537 s |
| Attack traffic reaching origin | 0.018% |
| Legitimate traffic challenged | 0.66% |
Timeline
The attack was preceded by a hacktivist channel announcing the target. Request rates on the targeted routes exceeded their hourly baseline by a factor of 290 within 25 seconds. The risk score of participating clients crossed the challenge threshold automatically and proof-of-work difficulty rose with origin load.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Enable log streaming to your SIEM for faster correlation.
- Review allow-listed partner ranges quarterly.