On Sunday 6 June 2021 at 17:02 UTC, a UDP reflection (DNS) targeted a airline booking customer in Southeast Asia. The attack peaked at 66.9 Gbps and lasted 76 minutes. Traffic originated from 1807 autonomous systems in 70 countries, predominantly compromised cloud VMs.
| Vector | UDP reflection (DNS) |
| Peak | 66.9 Gbps |
| Duration | 76 min |
| Time to mitigation | 0.732 s |
| Attack traffic reaching origin | 0.083% |
| Legitimate traffic challenged | 0.41% |
Timeline
The attack was preceded by a breaking political story. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 32 points of presence.
What the customer saw
The customer’s status page stayed green throughout; they learned about the attack from our notification.
Recommendations
- Review allow-listed partner ranges quarterly.
- Enable authenticated origin pulls.
- Enable log streaming to your SIEM for faster correlation.
How does the proof-of-work challenge behave on older Android devices? Any numbers below Android 10?
How does the proof-of-work challenge behave on older Android devices? Any numbers below Android 10?
We had the exact false-positive issue with CGNAT carriers. The weighting change makes sense.
Verified good bots and allow-listed partners bypass challenges entirely.
Solid runbook advice. The DNS-at-2am point hit home.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.
Is the risk score exposed in the logs so we can build our own dashboards on it?
Solid runbook advice. The DNS-at-2am point hit home.
How do you avoid challenging uptime monitors and partners?
Our auditors asked for exactly this kind of incident evidence under DORA.