Detection rules › Splunk
Windows KrbRelayUp Service Creation
The following analytic detects the creation of a service with the default name "KrbSCM" associated with the KrbRelayUp tool. It leverages Windows System Event Logs, specifically EventCode 7045, to identify this activity. This behavior is significant as KrbRelayUp is a known tool used for privilege escalation attacks. If confirmed malicious, this activity could allow an attacker to escalate privileges, potentially gaining unauthorized access to sensitive systems and data.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Persistence | T1543.003 Create or Modify System Process: Windows Service |
| Privilege Escalation | T1543.003 Create or Modify System Process: Windows Service |
Event coverage
| Provider | Event |
|---|---|
| Service-Control-Manager | Event ID 7045 |
Rule body splunk
name: Windows KrbRelayUp Service Creation
id: e40ef542-8241-4419-9af4-6324582ea60a
version: 11
creation_date: '2022-05-02'
modification_date: '2026-05-13'
author: Michael Haag, Splunk
status: production
type: TTP
description: The following analytic detects the creation of a service with the default name "KrbSCM" associated with the KrbRelayUp tool. It leverages Windows System Event Logs, specifically EventCode 7045, to identify this activity. This behavior is significant as KrbRelayUp is a known tool used for privilege escalation attacks. If confirmed malicious, this activity could allow an attacker to escalate privileges, potentially gaining unauthorized access to sensitive systems and data.
data_source:
- Windows Event Log System 7045
search: |-
`wineventlog_system` EventCode=7045 ServiceName IN ("KrbSCM")
| stats count min(_time) as firstTime max(_time) as lastTime
BY dest EventCode ImagePath
ServiceName StartType ServiceType
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_krbrelayup_service_creation_filter`
how_to_implement: To successfully implement this search, you need to be ingesting Windows System Event Logs with 7045 EventCode enabled. The Windows TA is also required.
known_false_positives: False positives should be limited as this is specific to KrbRelayUp based attack. Filter as needed.
references:
- https://github.com/Dec0ne/KrbRelayUp
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"
finding:
title: A service was created on $dest$, related to KrbRelayUp.
entity:
field: dest
type: system
score: 50
analytic_story:
- Local Privilege Escalation With KrbRelayUp
- Compromised Windows Host
asset_type: Endpoint
mitre_attack_id:
- T1543.003
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/attack_techniques/T1543.003/windows_krbrelayup_service_creation/windows-xml.log
source: XmlWinEventLog:System
sourcetype: XmlWinEventLog
test_type: unit
Stages and Predicates
Stage 1: search
`wineventlog_system` EventCode=7045 ServiceName IN ("KrbSCM")
Stage 2: stats
| stats count min(_time) as firstTime max(_time) as lastTime
BY dest EventCode ImagePath
ServiceName StartType ServiceType
Stage 3: search
| `security_content_ctime(firstTime)`
Stage 4: search
| `security_content_ctime(lastTime)`
Stage 5: search
| `windows_krbrelayup_service_creation_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 |
|
ServiceName | in |
|