ID | Technique | Tactic |
---|---|---|
T1190 | Exploit Public-Facing Application | Initial Access |
Detection: 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.
Search
1
2| 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
3| `drop_dm_object_name("Web")`
4| `security_content_ctime(firstTime)`
5| `security_content_ctime(lastTime)`
6| `jetbrains_teamcity_authentication_bypass_cve_2024_27198_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($field$) |
jetbrains_teamcity_authentication_bypass_cve_2024_27198_filter | search * |
jetbrains_teamcity_authentication_bypass_cve_2024_27198_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
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 |
Implementation
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
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
Possible JetBrains TeamCity Authentication Bypass CVE-2024-27198 Attempt against $dest$ from $src$. | 81 | 90 | 90 |
References
-
https://github.com/projectdiscovery/nuclei-templates/pull/9279/files
-
https://blog.jetbrains.com/teamcity/2024/03/teamcity-2023-11-4-is-out/
-
https://github.com/yoryio/CVE-2024-27198/blob/main/CVE-2024-27198.py
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: 3