Add vpatch-CVE-2023-38646 rule and test

[crowdsec-automation]

This rule targets the Metabase pre-auth RCE vulnerability (CVE-2023-38646) by detecting POST requests to the /api/setup/validate endpoint with a malicious H2 database subname parameter. The attack leverages the TRACE_LEVEL_SYSTEM_OUT=3;INIT=RUNSCRIPT sequence to trigger code execution via the H2 JDBC driver.

• The first rule condition matches the exact endpoint /api/setup/validate using a case-insensitive comparison.
• The second rule condition inspects the raw request body for the lowercased string trace_level_system_out=3;init=runscript, which is a reliable indicator of the exploit attempt, regardless of JSON structure or whitespace.
• The use of RAW_BODY ensures detection even if the JSON structure varies or is nested.
• The labels section includes the correct CVE, ATT&CK, and CWE references, and the label follows the required format.

All value: fields are lowercase, lowercase transform is applied, and contains is used for pattern matching to minimize false positives and negatives. No regex or capital letters are present in match values.

[github-actions]

Hello @crowdsec-automation and thank you for your contribution!

❗ It seems that the following scenarios are not part of the 'crowdsecurity/appsec-virtual-patching' collection:

🔴 crowdsecurity/vpatch-CVE-2023-38646 🔴

[github-actions]

Hello @crowdsec-automation and thank you for your contribution!

I'm a bot that helps maintainers to validate scenarios and ensure they include all the required information.
I've found some errors in your scenarios, please fix them and re-submit your PR, or ask for help if you need it.

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crowdsecurity/crs-exclusion-plugin-cpanel:

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crowdsecurity/crs-exclusion-plugin-drupal:

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crowdsecurity/crs-exclusion-plugin-nextcloud:

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crowdsecurity/crs-exclusion-plugin-phpmyadmin:

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crowdsecurity/crs-exclusion-plugin-xenforo:

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Mitre ATT&CK

Information about mitre attack can be found here.
As an example, some common mitre attack techniques:

• T1110 for bruteforce attacks
• T1595 and T1190 for exploitation of public vulnerabilities
• T1595 for generic scanning of exposed applications

Expected format is (where XXXX is the technique ID):

labels:
  classification:
    - attack.TXXXX

CVEs

If your scenario covers a specific CVE (Common Vulnerabilities and Exposures), please add it.

Expected format is (where CVE-XXX-XXX is the CVE ID):

labels:
  classification:
    - cve.CVE-XXX-XXX

Behaviors

Please identify the behavior(s) your scenario is targeting. You can find the list of available behaviors here.

Expected format is (where <behavior> is the behavior you want to target):

labels:
  behavior: <behavior>

See the labels documentation for more information.