""ET TROJAN Observed Malicious SSL Cert (DonotGroup CnC)""

SID: 2031617

Revision: 2

Class Type: trojan-activity

Metadata: affected_product Android, attack_target Client_and_Server, created_at 2021_02_12, deployment Perimeter, performance_impact Low, signature_severity Major, tag SSL_Malicious_Cert, updated_at 2021_02_12, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol

Reference:

Protocol: tcp

Source Network: $EXTERNAL_NET

Source Port: [443,4233]

Destination Network: $HOME_NET

Destination Port: any

Flow: from_server,established

Contents:

• Value: "|16|"

• Value: "|0b|"

• Value: "|55 04 03|"

• Value: "|0f|mobilelink.buzz"

• Value: "|55 04 0a|"

• Value: "|0d|Let's Encrypt"

Within: 14

PCRE:

Special Options:

• fast_pattern

source