Threat Bulletin 1059: CLDAP reflection against a education platform platform in the UK

On Wednesday 19 March 2025 at 13:40 UTC, a CLDAP reflection targeted a education platform customer in the UK. The attack peaked at 63.5 Gbps and lasted 128 minutes. Traffic originated from 232 autonomous systems in 13 countries, predominantly a rented booter service.

Vector CLDAP reflection
Peak 63.5 Gbps
Duration 128 min
Time to mitigation 0.188 s
Attack traffic reaching origin 0.059%
Legitimate traffic challenged 0.16%

Timeline

The attack was preceded by a ransom note demanding payment in Monero. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 31 points of presence.

What the customer saw

A brief increase in p99 latency of 95 ms during the first minute, then normal service.

Recommendations

  • Enable authenticated origin pulls.
  • Lower challenge thresholds on authentication endpoints during high-risk events.
  • Enable log streaming to your SIEM for faster correlation.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top