Detection: IcedID Exfiltrated Archived File Creation

Updated Date: 2024-10-17 ID: 0db4da70-f14b-11eb-8043-acde48001122 Author: Teoderick Contreras, Splunk Type: Hunting Product: Splunk Enterprise Security

Description

The following analytic detects the creation of suspicious files named passff.tar and cookie.tar, which are indicative of archived stolen browser information such as history and cookies on a machine compromised with IcedID. It leverages Sysmon EventCode 11 to identify these specific filenames. This activity is significant because it suggests that sensitive browser data has been exfiltrated, which could lead to further exploitation or data breaches. If confirmed malicious, this could allow attackers to access personal information, conduct further phishing attacks, or escalate their presence within the network.

1`sysmon` EventCode= 11  (TargetFilename = "*\\passff.tar" OR TargetFilename = "*\\cookie.tar") 
2|stats count min(_time) as firstTime max(_time) as lastTime by TargetFilename EventCode process_id  process_name dest 
3| `security_content_ctime(firstTime)` 
4| `security_content_ctime(lastTime)` 
5| `icedid_exfiltrated_archived_file_creation_filter`

Data Source

Name Platform Sourcetype Source
CrowdStrike ProcessRollup2 N/A 'crowdstrike:events:sensor' 'crowdstrike'
Sysmon EventID 1 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Windows Event Log Security 4688 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Security'

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
icedid_exfiltrated_archived_file_creation_filter search *
icedid_exfiltrated_archived_file_creation_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
T1560.001 Archive via Utility Collection
T1560 Archive Collected Data Collection
KillChainPhase.EXPLOITAITON
NistCategory.DE_AE
Cis18Value.CIS_10
APT1
APT28
APT3
APT33
APT39
APT41
APT5
Agrius
Akira
Aquatic Panda
BRONZE BUTLER
Chimera
CopyKittens
Earth Lusca
FIN13
FIN8
Fox Kitten
GALLIUM
Gallmaker
HAFNIUM
INC Ransom
Ke3chang
Kimsuky
Magic Hound
MuddyWater
Mustang Panda
Play
RedCurl
Sowbug
ToddyCat
Turla
Volt Typhoon
Wizard Spider
menuPass
APT28
APT32
Axiom
Dragonfly
Ember Bear
FIN6
Ke3chang
Lazarus Group
Leviathan
LuminousMoth
Patchwork
menuPass

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 Risk Event False
This configuration file applies to all detections of type hunting.

Implementation

To successfully implement this search, you need to be ingesting logs with the process name, parent process, and command-line executions from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.

Known False Positives

unknown

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Process $process_name$ create a file $TargetFilename$ on host $dest$ 72 80 90
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

References

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: 3