Threat Bulletin 0147: GRE flood against a municipal services platform in Latin America

On Monday 20 September 2021 at 06:21 UTC, a GRE flood targeted a municipal services customer in Latin America. The attack peaked at 273.4 Gbps and lasted 175 minutes. Traffic originated from 2621 autonomous systems in 109 countries, predominantly a Mirai-derived IoT botnet.

Vector GRE flood
Peak 273.4 Gbps
Duration 175 min
Time to mitigation 0.623 s
Attack traffic reaching origin 0.066%
Legitimate traffic challenged 0.26%

Timeline

The attack was preceded by an extortion email received two days earlier. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 30 points of presence.

What the customer saw

Checkout conversion was unchanged compared with the same hour of the previous week.

Recommendations

  • Review allow-listed partner ranges quarterly.
  • Add a dedicated rate limit for the targeted route.
  • Enable authenticated origin pulls.

Leave a Comment

Your email address will not be published.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

Scroll to Top