Windows Rapid Authentication On Multiple Hosts
Description
The following analytic leverages Event ID 4624 to identify a source computer authenticating to a large number of remote endpoints within an Active Directory network. Specifically, the logic will trigger when a source endpoint authenticates to 30 or more target computers within a 5 minute timespan. This behavior could represent an adversary who is moving laterally across the environment or enumerating network shares in the search for sensitive files. As environments differ across organizations, security teams should customize the thresholds of this detection as needed.
- Type: TTP
-
Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Last Updated: 2023-03-23
- Author: Mauricio Velazco, Splunk
- ID: 62606c77-d53d-4182-9371-b02cdbbbcef7
Annotations
Kill Chain Phase
- Exploitation
NIST
- DE.CM
CIS20
- CIS 10
CVE
Search
1
2
3
4
5
`wineventlog_security` EventCode=4624 LogonType=3 TargetUserName!="ANONYMOUS LOGON" TargetUserName!="*$"
| bucket span=5m _time
| stats dc(Computer) AS unique_targets values(Computer) as host_targets by _time, IpAddress, TargetUserName
| where unique_targets > 30
| `windows_rapid_authentication_on_multiple_hosts_filter`
Macros
The SPL above uses the following Macros:
windows_rapid_authentication_on_multiple_hosts_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Required fields
List of fields required to use this analytic.
- _time
- EventCode
- Logon_Type
- TargetUserName
- Computer
- IpAddress
How To Implement
To successfully implement this search, you need to be ingesting Windows Event Logs from domain controllers as well as member servers and workstations. The Advanced Security Audit policy setting Audit Logon
within Logon/Logoff
needs to be enabled.
Known False Positives
Vulnerability scanners or system administration tools may also trigger this detection. Filter as needed.
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
48.0 | 60 | 80 | The source computer with ip address $IpAddress$ authenticated to a large number of remote endpoints within 5 minutes. |
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
Reference
- https://attack.mitre.org/techniques/T1135/
- https://thedfirreport.com/2023/01/23/sharefinder-how-threat-actors-discover-file-shares/
- https://learn.microsoft.com/en-us/windows/security/threat-protection/auditing/event-4624
Test Dataset
Replay any dataset to Splunk Enterprise by using our replay.py
tool or the UI.
Alternatively you can replay a dataset into a Splunk Attack Range
source | version: 1