Detection rules › Splunk
Windows Terminating Lsass Process
The following analytic detects a suspicious process attempting to terminate the Lsass.exe process. It leverages Sysmon EventCode 10 logs to identify processes granted PROCESS_TERMINATE access to Lsass.exe. This activity is significant because Lsass.exe is a critical process responsible for enforcing security policies and handling user credentials. If confirmed malicious, this behavior could indicate an attempt to perform credential dumping, privilege escalation, or evasion of security policies, potentially leading to unauthorized access and persistence within the environment.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Defense Impairment | T1685 Disable or Modify Tools |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 10 | ProcessAccess |
Rule body splunk
name: Windows Terminating Lsass Process
id: 7ab3c319-a4e7-4211-9e8c-40a049d0dba6
version: 15
creation_date: '2022-03-28'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: The following analytic detects a suspicious process attempting to terminate the Lsass.exe process. It leverages Sysmon EventCode 10 logs to identify processes granted PROCESS_TERMINATE access to Lsass.exe. This activity is significant because Lsass.exe is a critical process responsible for enforcing security policies and handling user credentials. If confirmed malicious, this behavior could indicate an attempt to perform credential dumping, privilege escalation, or evasion of security policies, potentially leading to unauthorized access and persistence within the environment.
data_source:
- Sysmon EventID 10
search: |-
`sysmon` EventCode=10 TargetImage=*lsass.exe GrantedAccess = 0x1
| stats count min(_time) as firstTime max(_time) as lastTime
BY CallTrace EventID GrantedAccess
Guid Opcode ProcessID
SecurityID SourceImage SourceProcessGUID
SourceProcessId TargetImage TargetProcessGUID
TargetProcessId UserID dest
granted_access parent_process_exec parent_process_guid
parent_process_id parent_process_name parent_process_path
process_exec process_guid process_id
process_name process_path signature
signature_id user_id vendor_product
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_terminating_lsass_process_filter`
how_to_implement: This search requires Sysmon Logs and a Sysmon configuration, which includes EventCode 10 for lsass.exe. This search uses an input macro named `sysmon`. We strongly recommend that you specify your environment-specific configurations (index, source, sourcetype, etc.) for Windows Sysmon logs. Replace the macro definition with configurations for your Splunk environment. The search also uses a post-filter macro designed to filter out known false positives.
known_false_positives: No false positives have been identified at this time.
references:
- https://blog.talosintelligence.com/2022/03/threat-advisory-doublezero.html
drilldown_searches:
- name: View the detection results for - "$dest$"
search: '%original_detection_search% | search dest = "$dest$"'
earliest_offset: $info_min_time$
latest_offset: $info_max_time$
- name: View risk events for the last 7 days for - "$dest$"
search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
earliest_offset: 7d
latest_offset: "0"
intermediate_findings:
entities:
- field: dest
type: system
score: 20
message: a process $SourceImage$ terminates Lsass process on $dest$
threat_objects:
- field: TargetImage
type: process
analytic_story:
- Data Destruction
- Double Zero Destructor
- Scattered Lapsus$ Hunters
asset_type: Endpoint
mitre_attack_id:
- T1685
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/malware/doublezero_wiper/sysmon.log
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
sourcetype: XmlWinEventLog
test_type: unit
Stages and Predicates
Stage 1: search
`sysmon` EventCode=10 TargetImage=*lsass.exe GrantedAccess = 0x1
Stage 2: stats
| stats count min(_time) as firstTime max(_time) as lastTime
BY CallTrace EventID GrantedAccess
Guid Opcode ProcessID
SecurityID SourceImage SourceProcessGUID
SourceProcessId TargetImage TargetProcessGUID
TargetProcessId UserID dest
granted_access parent_process_exec parent_process_guid
parent_process_id parent_process_name parent_process_path
process_exec process_guid process_id
process_name process_path signature
signature_id user_id vendor_product
Stage 3: search
| `security_content_ctime(firstTime)`
Stage 4: search
| `security_content_ctime(lastTime)`
Stage 5: search
| `windows_terminating_lsass_process_filter`
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
EventCode | eq |
|
GrantedAccess | eq |
|
TargetImage | eq |
|