IMPORTANT: No additional bug fixes or documentation updates
will be released for this version. For the latest information, see the
current release documentation.
Suspicious Process Access via Direct System Call
editSuspicious Process Access via Direct System Call
editIdentifies suspicious process access events from an unknown memory region. Endpoint security solutions usually hook userland Windows APIs in order to decide if the code that is being executed is malicious or not. It’s possible to bypass hooked functions by writing malicious functions that call syscalls directly.
Rule type: eql
Rule indices:
- winlogbeat-*
- logs-windows.*
Severity: high
Risk score: 73
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Host
- Windows
- Threat Detection
- Defense Evasion
Version: 2
Rule authors:
- Elastic
Rule license: Elastic License v2
Rule query
editprocess where event.code == "10" and
length(winlog.event_data.CallTrace) > 0 and
/* Sysmon CallTrace starting with unknown memory module instead of ntdll which host Windows NT Syscalls */
not winlog.event_data.CallTrace : ("?:\\WINDOWS\\SYSTEM32\\ntdll.dll*", "?:\\WINDOWS\\SysWOW64\\ntdll.dll*")
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
-
Technique:
- Name: Process Injection
- ID: T1055
- Reference URL: https://attack.mitre.org/techniques/T1055/