""ET INFO 404/Snake/Matiex Keylogger Style External IP Check""

SID: 2039190

Revision: 4

Class Type: misc-activity

Metadata: affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2020_05_13, deployment Perimeter, malware_family 404Keylogger, signature_severity Informational, updated_at 2023_05_24

Reference:

  • md5

  • 017e7b6b886cce51eb03ce097c1a4c80

Protocol: tcp

Source Network: $HOME_NET

Source Port: any

Destination Network: $EXTERNAL_NET

Destination Port: $HTTP_PORTS

Flow: established,to_server

Contents:

  • Value: "GET"

  • Value: "User-Agent|3a 20|Mozilla/4.0 (compatible|3b 20|MSIE 6.0|3b 20|Windows NT 5.2|3b 20|.NET CLR1.0.3705|3b|)|0d 0a|Host|3a 20|checkip.dyndns.org|0d 0a|Connection|3a 20|Keep-Alive|0d 0a 0d 0a|"

  • Value: "|0d 0a|Host|3a 20|checkip.dyndns.org|0d 0a|"

Within:

PCRE: "/^User-Agent\x3a\x20[^\r\n]+\r\nHost\x3a\x20[^\r\n]+\r\nConnection\x3a\x20[^\r\n]+\r\n\r\n$/Hmi"

Special Options:

  • http_method

  • http_header

  • fast_pattern

  • http_header

source