""ET INFO Observed DNS over HTTPS Domain in TLS SNI (basic .rethinkdns .com)""

SID: 2048507

Revision: 2

Class Type: misc-activity

Metadata: attack_target Client_Endpoint, created_at 2022_02_09, deployment Perimeter, signature_severity Informational, tag DoH, updated_at 2023_10_10, former_sid 2851065, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1572, mitre_technique_name Protocol_Tunneling

Reference:

Protocol: tcp

Source Network: $HOME_NET

Source Port: any

Destination Network: $EXTERNAL_NET

Destination Port: 443

Flow: established,to_server

Contents:

  • Value: "|16|"

  • Value: "|01|"

  • Value: "|00 00 14|basic.rethinkdns.com"

Within: 8

PCRE:

Special Options:

  • fast_pattern

source