Outbound Network Connection To Public IP Via Winlogon

 1title: Outbound Network Connection To Public IP Via Winlogon
 2id: 7610a4ea-c06d-495f-a2ac-0a696abcfd3b
 3status: test
 4description: Detects a "winlogon.exe" process that initiate network communications with public IP addresses
 5references:
 6    - https://www.microsoft.com/en-us/security/blog/2023/04/11/guidance-for-investigating-attacks-using-cve-2022-21894-the-blacklotus-campaign/
 7author: Christopher Peacock @securepeacock, SCYTHE @scythe_io
 8date: 2023-04-28
 9modified: 2024-03-12
10tags:
11    - attack.defense-evasion
12    - attack.execution
13    - attack.command-and-control
14    - attack.t1218.011
15logsource:
16    category: network_connection
17    product: windows
18detection:
19    selection:
20        Image|endswith: '\winlogon.exe'
21        Initiated: 'true'
22    filter_main_local_ranges:
23        DestinationIp|cidr:
24            - '127.0.0.0/8'
25            - '10.0.0.0/8'
26            - '172.16.0.0/12'
27            - '192.168.0.0/16'
28            - '169.254.0.0/16'
29            - '::1/128'  # IPv6 loopback
30            - 'fe80::/10'  # IPv6 link-local addresses
31            - 'fc00::/7'  # IPv6 private addresses
32    condition: selection and not 1 of filter_main_*
33falsepositives:
34    - Communication to other corporate systems that use IP addresses from public address spaces
35level: medium