1type: trigger
2name: sigmahq/proc_creation_win_browsers_chromium_susp_load_extension
3description: |
4  Detects a suspicious process spawning a Chromium based browser process with the 'load-extension' flag to start an instance with a custom extension
5filter: |
6  (evt.Meta.service == 'sysmon' && evt.Parsed.EventID == '1') && ((evt.Parsed.ParentImage endsWith '\\cmd.exe' || evt.Parsed.ParentImage endsWith '\\cscript.exe' || evt.Parsed.ParentImage endsWith '\\mshta.exe' || evt.Parsed.ParentImage endsWith '\\powershell.exe' || evt.Parsed.ParentImage endsWith '\\pwsh.exe' || evt.Parsed.ParentImage endsWith '\\regsvr32.exe' || evt.Parsed.ParentImage endsWith '\\rundll32.exe' || evt.Parsed.ParentImage endsWith '\\wscript.exe') && (evt.Parsed.Image endsWith '\\brave.exe' || evt.Parsed.Image endsWith '\\chrome.exe' || evt.Parsed.Image endsWith '\\msedge.exe' || evt.Parsed.Image endsWith '\\opera.exe' || evt.Parsed.Image endsWith '\\vivaldi.exe') && evt.Parsed.CommandLine contains '--load-extension=')
7blackhole: 2m
8#status: test
9labels:
10  service: windows
11  confidence: 1
12  spoofable: 0
13  classification:
14   - attack.t1176
15
16  label: "Suspicious Chromium Browser Instance Executed With Custom Extension"
17  behavior : "windows:audit"
18  remediation: false
19
20scope:
21  type: ParentProcessId
22  expression: evt.Parsed.ParentProcessId
23
24