Detection: Ivanti Sentry Authentication Bypass

Updated Date: 2024-05-17 ID: b8e0d1cf-e6a8-4d46-a5ae-aebe18ead8f8 Author: Michael Haag, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic identifies unauthenticated access attempts to the System Manager Portal in Ivanti Sentry, exploiting CVE-2023-38035. It detects this activity by monitoring HTTP requests to specific endpoints ("/mics/services/configservice/", "/mics/services/", "/mics/services/MICSLogService*") with a status code of 200. This behavior is significant for a SOC as it indicates potential unauthorized access, which could lead to OS command execution as root. If confirmed malicious, this activity could result in significant system compromise and data breaches, especially if port 8443 is exposed to the internet.

1
2| tstats count min(_time) as firstTime max(_time) as lastTime from datamodel=Web where Web.url IN ("/mics/services/configservice/*", "/mics/services/*","/mics/services/MICSLogService*") Web.status=200 by Web.http_user_agent, Web.status Web.http_method, Web.url, Web.url_length, Web.src, Web.dest, sourcetype 
3| `drop_dm_object_name("Web")` 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `ivanti_sentry_authentication_bypass_filter`

Data Source

Name Platform Sourcetype Source Supported App
Suricata N/A 'suricata' 'suricata' N/A

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
ivanti_sentry_authentication_bypass_filter search *
ivanti_sentry_authentication_bypass_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
T1190 Exploit Public-Facing Application Initial Access
KillChainPhase.DELIVERY
NistCategory.DE_CM
Cis18Value.CIS_13
APT28
APT29
APT39
APT41
APT5
Axiom
BackdoorDiplomacy
BlackTech
Blue Mockingbird
Cinnamon Tempest
Dragonfly
Earth Lusca
FIN13
FIN7
Fox Kitten
GALLIUM
GOLD SOUTHFIELD
HAFNIUM
Ke3chang
Kimsuky
Magic Hound
Moses Staff
MuddyWater
Rocke
Sandworm Team
Threat Group-3390
ToddyCat
Volatile Cedar
Volt Typhoon
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

To implement this analytic, a network product similar to Suricata or Palo Alto needs to be mapped to the Web datamodel. Modify accordingly to work with your products.

Known False Positives

It is important to note that false positives may occur if the search criteria are expanded beyond the HTTP status code 200. In other words, if the search includes other HTTP status codes, the likelihood of encountering false positives increases. This is due to the fact that HTTP status codes other than 200 may not necessarily indicate a successful exploitation attempt.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Possible exploitation of CVE-2023-38035 against $dest$. 45 90 50
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 suricata suricata
Integration ✅ Passing Dataset suricata suricata

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: 2