""ET INFO Observed URL Shortener Domain (lk .tc in TLS SNI)""

SID: 2035743

Revision: 2

Class Type: misc-activity

Metadata: affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2022_04_04, deployment Perimeter, signature_severity Informational, updated_at 2022_04_04

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|"

  • Value: "|00|"

  • Value: "lk.tc"

Within: 1

PCRE: "/^(?:\x00\x05|.\x2e)lk.tc/R"

Special Options:

source