Detection: Path traversal SPL injection

Description

The following analytic identifies attempts at path traversal in search parameters, which can lead to SPL injection. It detects this activity by searching for specific patterns in the _internal index that indicate path traversal attempts (e.g., "../../../../"). This activity is significant for a SOC because it can allow an attacker to manipulate the application to load data from incorrect endpoints, potentially running arbitrary SPL queries. If confirmed malicious, this could lead to unauthorized data access, code execution, or further exploitation of the Splunk environment.

1`path_traversal_spl_injection` 
2| search "\/..\/..\/..\/..\/..\/..\/..\/..\/..\/"  
3| stats count by host status clientip method uri_path uri_query 
4| `path_traversal_spl_injection_filter`

Data Source

Name Platform Sourcetype Source Supported App
Splunk Splunk icon Splunk 'splunkd_ui_access' 'splunkd_ui_access.log' N/A

Macros Used

Name Value
path_traversal_spl_injection index=_internal sourcetype=splunkd_ui_access
path_traversal_spl_injection_filter search *
path_traversal_spl_injection_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
T1083 File and Directory Discovery Discovery
KillChainPhase.EXPLOITAITON
NistCategory.DE_CM
Cis18Value.CIS_10
APT18
APT28
APT3
APT32
APT38
APT39
APT41
APT5
Aoqin Dragon
BRONZE BUTLER
Chimera
Confucius
Dark Caracal
Darkhotel
Dragonfly
FIN13
Fox Kitten
Gamaredon Group
HAFNIUM
Inception
Ke3chang
Kimsuky
Lazarus Group
Leafminer
LuminousMoth
Magic Hound
MuddyWater
Mustang Panda
Patchwork
Sandworm Team
Scattered Spider
Sidewinder
Sowbug
TeamTNT
ToddyCat
Tropic Trooper
Turla
Windigo
Winnti Group
admin@338
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 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 detection does not require you to ingest any new data. The detection does require the ability to search the _internal index. This search will provide search UI requests with path traversal parameter ("../../../../../../../../../") which shows exploitation attempts. This detection is meant for on premise environments, and if executed on internet facing servers without a WAF may produce a lot of results. This detection will not work against obfuscated path traversal requests.

Known False Positives

This search may find additional path traversal exploitation attempts.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Path traversal exploitation attempt from $clientip$ 40 50 80
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 splunkd_ui_access.log splunkd_ui_access
Integration ✅ Passing Dataset splunkd_ui_access.log splunkd_ui_access

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: 4