JetBrains TeamCity Authentication Bypass CVE-2024-27198
Description
The following analytic identifies attempts to exploit the JetBrains TeamCity Authentication Bypass vulnerability (CVE-2024-27198). It detects suspicious POST requests to the /app/rest/users
and /app/rest/users/id:1/tokens
endpoints, which are indicative of attempts to create new administrator users or generate admin access tokens without authentication. This detection leverages the Web datamodel and CIM-compliant log sources, such as Nginx or TeamCity logs. This activity is significant as it can lead to full control over the TeamCity server, including all projects, builds, agents, and artifacts. If confirmed malicious, attackers could gain unauthorized administrative access, leading to severe security breaches.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Web
- Last Updated: 2024-05-20
- Author: Michael Haag, Splunk
- ID: fbcc04c7-8a79-453c-b3a9-c232c423bdd4
Annotations
Kill Chain Phase
- Delivery
NIST
- DE.CM
CIS20
- CIS 13
CVE
Search
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| tstats count min(_time) as firstTime max(_time) as lastTime from datamodel=Web where ((Web.url="*?jsp=*" AND Web.url="*;.jsp*") Web.status=200 Web.http_method=POST) OR (Web.url IN ("*jsp=/app/rest/users;.jsp","*?jsp=/app/rest/users;.jsp","*?jsp=.*/app/rest/users/id:*/tokens;*") Web.status=200 Web.http_method=POST ) by Web.src, Web.dest, Web.http_user_agent, Web.url, Web.status, Web.http_method, sourcetype, source
| `drop_dm_object_name("Web")`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `jetbrains_teamcity_authentication_bypass_cve_2024_27198_filter`
Macros
The SPL above uses the following Macros:
jetbrains_teamcity_authentication_bypass_cve-2024-27198_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.
- Web.src
- Web.dest
- Web.http_user_agent
- Web.url
- Web.status
- Web.http_method
- sourcetype
- source
How To Implement
The detection relies on the Web datamodel and a CIM compliant log source, that may include Nginx, TeamCity logs, or other web server logs.
Known False Positives
False positives are not expected, as this detection is based on the presence of specific URI paths and HTTP methods that are indicative of the CVE-2024-27198 vulnerability exploitation. Monitor, filter and tune as needed based on organization log sources.
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
81.0 | 90 | 90 | Possible JetBrains TeamCity Authentication Bypass CVE-2024-27198 Attempt against $dest$ from $src$. |
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/projectdiscovery/nuclei-templates/pull/9279/files
- https://www.rapid7.com/blog/post/2024/03/04/etr-cve-2024-27198-and-cve-2024-27199-jetbrains-teamcity-multiple-authentication-bypass-vulnerabilities-fixed/
- https://blog.jetbrains.com/teamcity/2024/03/teamcity-2023-11-4-is-out/
- https://blog.jetbrains.com/teamcity/2024/03/additional-critical-security-issues-affecting-teamcity-on-premises-cve-2024-27198-and-cve-2024-27199-update-to-2023-11-4-now/
- https://github.com/yoryio/CVE-2024-27198/blob/main/CVE-2024-27198.py
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