""ET TROJAN [ANY.RUN] Win32/ObserverStealer CnC Activity (Loading) M1""

SID: 2046169

Revision: 1

Class Type: trojan-activity

Metadata: affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2023_06_07, deployment Perimeter, malware_family ObserverStealer, performance_impact Moderate, confidence High, signature_severity Critical, updated_at 2023_06_08

Reference:

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: "/?id=" Depth: 5

  • Value: "User-Agent|3a 20|Mozilla|2f|4|2e|0|20 28|compatible|3b 20|MSIE|20|7|2e|0|3b 20|Windows|20|NT|20|6|2e|3|3b 20|WOW64|3b 20|Trident|2f|7|2e|0|3b 20 2e|NET4|2e|0C|3b 20 2e|NET4|2e|0E|3b 20 2e|NET|20|CLR|20|2|2e|0|2e|50727|3b 20 2e|NET|20|CLR|20|3|2e|0|2e|30729|3b 20 2e|NET|20|CLR|20|3|2e|5|2e|30729|29 0d 0a|"

  • Value: "Accept|3a 20 2a 2f 2a 0d 0a|"

  • Value: "Accept-Encoding|3a 20|gzip|2c 20|deflate|0d 0a|"

  • Value: "Connection|3a 20|Keep-Alive|0d 0a|"

Within:

PCRE: "/Host\x3a\x20(?:(?:\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5]).){3}(?:\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5])(:\d{2,5})?/H"

Special Options:

  • http_method

  • http_uri

  • fast_pattern

  • http_header

  • http_header

  • http_header

  • http_header

source