Detection: Detect Credential Dumping through LSASS access

Updated Date: 2024-11-13 ID: 2c365e57-4414-4540-8dc0-73ab10729996 Author: Patrick Bareiss, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic detects attempts to read LSASS memory, indicative of credential dumping. It leverages Sysmon EventCode 10, filtering for specific access permissions (0x1010 and 0x1410) on the lsass.exe process. This activity is significant because it suggests an attacker is trying to extract credentials from LSASS memory, potentially leading to unauthorized access, data breaches, and compromise of sensitive information. If confirmed malicious, this could enable attackers to escalate privileges, move laterally within the network, or exfiltrate data. Extensive triage is necessary to differentiate between malicious and benign activities.

Search

1`sysmon` EventCode=10 TargetImage=*lsass.exe (GrantedAccess=0x1010 OR GrantedAccess=0x1410) 
2| stats count min(_time) as firstTime max(_time) as lastTime by dest, SourceImage, SourceProcessId, TargetImage, TargetProcessId, EventCode, GrantedAccess 
3| `security_content_ctime(firstTime)`
4| `security_content_ctime(lastTime)` 
5| `detect_credential_dumping_through_lsass_access_filter`

Data Source

Name	Platform	Sourcetype	Source
Sysmon EventID 10	Windows	`'xmlwineventlog'`	`'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'`

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
detect_credential_dumping_through_lsass_access_filter	`search *`

detect_credential_dumping_through_lsass_access_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1003.001	LSASS Memory	Credential Access
T1003	OS Credential Dumping	Credential Access

Exploitation

DE.CM

CIS 10

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Notable	Yes
Rule Title	`%name%`
Rule Description	`%description%`
Notable Event Fields	user, dest
Creates Risk Event	True

This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.

Implementation

This search needs Sysmon Logs and a sysmon configuration, which includes EventCode 10 with 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

The activity may be legitimate. Other tools can access lsass for legitimate reasons, and it's possible this event could be generated in those cases. In these cases, false positives should be fairly obvious and you may need to tweak the search to eliminate noise.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

The $SourceImage$ has attempted access to read $TargetImage$ was identified on endpoint $dest$, this is indicative of credential dumping and should be investigated.

Risk Object	Risk Object Type	Risk Score	Threat Objects
dest	system	80	No Threat Objects

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-Sysmon/Operational`	`XmlWinEventLog`
Integration	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-Sysmon/Operational`	`XmlWinEventLog`

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: GitHub | Version: 6