diff --git a/etc/non-ecs-schema.json b/etc/non-ecs-schema.json index 81e5f2144..f3a8b980e 100644 --- a/etc/non-ecs-schema.json +++ b/etc/non-ecs-schema.json @@ -11,6 +11,8 @@ "winlog.event_data.OriginalFileName": "keyword", "winlog.event_data.GrantedAccess": "keyword", "winlog.event_data.CallTrace": "keyword", + "powershell.file.script_block_text": "text", + "winlog.event_data.TargetProcessGUID": "keyword", "powershell.file.script_block_text": "text", "winlog.event_data.CallerProcessName": "keyword", "winlog.event_data.TargetSid": "keyword", diff --git a/rules/windows/defense_evasion_suspicious_process_creation_calltrace.toml b/rules/windows/defense_evasion_suspicious_process_creation_calltrace.toml new file mode 100644 index 000000000..5ab67a492 --- /dev/null +++ b/rules/windows/defense_evasion_suspicious_process_creation_calltrace.toml @@ -0,0 +1,50 @@ +[metadata] +creation_date = "2021/10/24" +maturity = "production" +updated_date = "2021/10/24" + +[rule] +author = ["Elastic"] +description = """ +Identifies when a process is created and immediately accessed from an unknown memory code region and by the same parent +process. This may indicate a code injection or hollowing attempt. +""" +from = "now-9m" +index = ["winlogbeat-*", "logs-windows.*"] +language = "eql" +license = "Elastic License v2" +name = "Suspicious Process Creation CallTrace" +risk_score = 43 +rule_id = "3ed032b2-45d8-4406-bc79-7ad1eabb2c72" +severity = "medium" +tags = ["Elastic", "Host", "Windows", "Threat Detection", "Defense Evasion"] +timestamp_override = "event.ingested" +type = "eql" + +query = ''' +sequence by host.id with maxspan=1m + [process where event.code == "1" and + /* sysmon process creation */ + process.parent.name : ("winword.exe", "excel.exe", "outlook.exe", "powerpnt.exe", "eqnedt32.exe", + "fltldr.exe", "mspub.exe", "msaccess.exe", "powershell.exe", "pwsh.exe", + "cscript.exe", "wscript.exe", "rundll32.exe", "regsvr32.exe", "mshta.exe", + "wmic.exe", "cmstp.exe", "msxsl.exe")] by process.parent.entity_id, process.entity_id + [process where event.code == "10" and + /* Sysmon process access event from unknown module */ + winlog.event_data.CallTrace : "*UNKNOWN*"] by process.entity_id, winlog.event_data.TargetProcessGUID +''' + + +[[rule.threat]] +framework = "MITRE ATT&CK" +[[rule.threat.technique]] +name = "Process Injection" +id = "T1055" +reference = "https://attack.mitre.org/techniques/T1055/" + + +[rule.threat.tactic] +name = "Defense Evasion" +id = "TA0005" +reference = "https://attack.mitre.org/tactics/TA0005/" +