Detection: Linux Auditd Find Credentials From Password Managers

Description

The following analytic detects suspicious attempts to find credentials stored in password managers, which may indicate an attacker's effort to retrieve sensitive login information. Password managers are often targeted by adversaries seeking to access stored passwords for further compromise or lateral movement within a network. By monitoring for unusual or unauthorized access to password manager files or processes, this analytic helps identify potential credential theft attempts, enabling security teams to respond quickly to protect critical accounts and prevent further unauthorized access.

1`linux_auditd` `linux_auditd_normalized_execve_process` 
2| rename host as dest 
3| rename comm as process_name 
4| rename exe as process 
5| where  (LIKE (process_exec, "%find%") OR LIKE (process_exec, "%grep%")) AND (LIKE (process_exec, "%.kdbx%") OR LIKE (process_exec, "%KeePass%") OR LIKE (process_exec, "%KeePass\.enforced%") OR LIKE (process_exec, "%.lpdb%")OR LIKE (process_exec, "%.opvault%")OR LIKE (process_exec, "%.agilekeychain%")OR LIKE (process_exec, "%.dashlane%")OR LIKE (process_exec, "%.rfx%")OR LIKE (process_exec, "%passbolt%")OR LIKE (process_exec, "%.spdb%")OR LIKE (process_exec, "%StickyPassword%")OR LIKE (process_exec, "%.walletx%")OR LIKE (process_exec, "%enpass%")OR LIKE (process_exec, "%vault%")OR LIKE (process_exec, "%.kdb%")) 
6| stats count min(_time) as firstTime max(_time) as lastTime by argc process_exec dest 
7| `security_content_ctime(firstTime)` 
8| `security_content_ctime(lastTime)`
9| `linux_auditd_find_credentials_from_password_managers_filter`

Data Source

Name Platform Sourcetype Source
Linux Auditd Execve Linux icon Linux 'linux:audit' '/var/log/audit/audit.log'

Macros Used

Name Value
linux_auditd sourcetype="linux:audit"
linux_auditd_find_credentials_from_password_managers_filter search *
linux_auditd_find_credentials_from_password_managers_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
T1555.005 Password Managers Credential Access
T1555 Credentials from Password Stores 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

To implement this detection, the process begins by ingesting auditd data, that consists of SYSCALL, TYPE, EXECVE and PROCTITLE events, which captures command-line executions and process details on Unix/Linux systems. These logs should be ingested and processed using Splunk Add-on for Unix and Linux (https://splunkbase.splunk.com/app/833), which is essential for correctly parsing and categorizing the data. The next step involves normalizing the field names to match the field names set by the Splunk Common Information Model (CIM) to ensure consistency across different data sources and enhance the efficiency of data modeling. This approach enables effective monitoring and detection of linux endpoints where auditd is deployed

Known False Positives

Administrator or network operator can use this application for automation purposes. Please update the filter macros to remove false positives.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

A [$process_exec$] event occurred on host - [$dest$] to find credentials stored in password managers.

Risk Object Risk Object Type Risk Score Threat Objects
dest system 64 No Threat Objects

References

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation Passing N/A N/A N/A
Unit Passing Dataset /var/log/audit/audit.log linux:audit
Integration ✅ Passing Dataset /var/log/audit/audit.log linux:audit

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: 3