Detection: Access to Vulnerable Ivanti Connect Secure Bookmark Endpoint

Description

The following analytic identifies access to the /api/v1/configuration/users/user-roles/user-role/rest-userrole1/web/web-bookmarks/bookmark endpoint, which is associated with CVE-2023-46805 and CVE-2024-21887 vulnerabilities. It detects this activity by monitoring for GET requests that receive a 403 Forbidden response with an empty body. This behavior is significant as it indicates potential exploitation attempts against Ivanti Connect Secure systems. If confirmed malicious, attackers could exploit these vulnerabilities to gain unauthorized access or control over the affected systems, leading to potential data breaches or system compromise.

1
2| tstats count min(_time) as firstTime max(_time) as lastTime from datamodel=Web where Web.url="*/api/v1/configuration/users/user-roles/user-role/rest-userrole1/web/web-bookmarks/bookmark*" Web.http_method=GET Web.status=403 by Web.src, Web.dest, Web.http_user_agent, Web.status, Web.url source 
3| `drop_dm_object_name("Web")` 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `access_to_vulnerable_ivanti_connect_secure_bookmark_endpoint_filter`

Data Source

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

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
access_to_vulnerable_ivanti_connect_secure_bookmark_endpoint_filter search *
access_to_vulnerable_ivanti_connect_secure_bookmark_endpoint_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
Delivery
DE.CM
CIS 13

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 requires the Web datamodel to be populated from a supported Technology Add-On like Suricata, Splunk for Apache, Splunk for Nginx, or Splunk for Palo Alto.

Known False Positives

This analytic is limited to HTTP Status 403; adjust as necessary. False positives may occur if the URI path is IP-restricted or externally blocked. It's recommended to review the context of the alerts and adjust the analytic parameters to better fit the specific environment.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

Possible exploitation of CVE-2023-46805 and CVE-2024-21887 against $dest$.

Risk Object Risk Object Type Risk Score Threat Objects
dest system 72 No Threat Objects

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: 4