""ET TROJAN Possible CryptXXX Ransomware Renaming Encrypted File SMB v2""

SID: 2022840

Revision: 2

Class Type: trojan-activity

Metadata: attack_target Client_Endpoint, created_at 2016_05_25, deployment Perimeter, signature_severity Major, tag Ransomware, updated_at 2017_05_30, mitre_tactic_id TA0040, mitre_tactic_name Impact, mitre_technique_id T1486, mitre_technique_name Data_Encrypted_for_Impact

Reference:

Protocol: tcp

Source Network: $HOME_NET

Source Port: any

Destination Network: $EXTERNAL_NET

Destination Port: [445,139]

Flow: to_server,established

Contents:

  • Value: "|FE|SMB" Depth: 4 Offset: 4

  • Value: "|11 00|"

  • Value: "|00|.|00|c|00|r|00|y|00|p|00|t|00|"

Within: 2

PCRE: "/^[^A-Za-z0-9]/R"

Special Options:

  • nocase

  • fast_pattern

source