Web Spring Cloud Function FunctionRouter
Description
The following analytic identifies HTTP POST requests to the Spring Cloud Function endpoint containing "functionRouter" in the URL. It leverages the Web data model to detect these requests based on specific fields such as http_method, url, and http_user_agent. This activity is significant because it targets CVE-2022-22963, a known vulnerability in Spring Cloud Function, which has multiple proof-of-concept exploits available. If confirmed malicious, this activity could allow attackers to execute arbitrary code, potentially leading to unauthorized access, data exfiltration, or further compromise of the affected system.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Web
- Last Updated: 2024-05-22
- Author: Michael Haag, Splunk
- ID: 89dddbad-369a-4f8a-ace2-2439218735bc
Annotations
ATT&CK
Kill Chain Phase
- Delivery
- Installation
NIST
- DE.CM
CIS20
- CIS 13
CVE
Search
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| tstats count from datamodel=Web where Web.http_method IN ("POST") Web.url="*/functionRouter*" by Web.http_user_agent Web.http_method, Web.url,Web.url_length Web.src, Web.dest Web.status sourcetype
| `drop_dm_object_name("Web")`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `web_spring_cloud_function_functionrouter_filter`
Macros
The SPL above uses the following Macros:
web_spring_cloud_function_functionrouter_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Required fields
List of fields required to use this analytic.
- _time
- Web.http_method
- Web.url
- Web.url_length
- Web.src
- Web.dest
- Web.http_user_agent
How To Implement
To successfully implement this search you need to be ingesting information on Web traffic that include fields relavent for traffic into the Web
datamodel.
Known False Positives
False positives may be present with legitimate applications. Attempt to filter by dest IP or use Asset groups to restrict to servers.
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
42.0 | 70 | 60 | A suspicious URL has been requested against $dest$ by $src$, related to a vulnerability in Spring Cloud. |
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
Reference
- https://github.com/rapid7/metasploit-framework/pull/16395
- https://github.com/hktalent/spring-spel-0day-poc
Test Dataset
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 | version: 2