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CVE-2026-54617 IBM QRadar · QRadar

Detect LaunchServer FileServerHandler Unauthenticated Path Traversal (CVE-2026-54617) in IBM QRadar

Detects exploitation attempts against pro.gravit.launcher:launchserver-api's FileServerHandler, which is vulnerable to an unauthenticated path traversal (CWE-22) allowing arbitrary file read (CWE-200) and disclosure of sensitive data such as credentials or keys (CWE-522) in versions <= 5.7.11. Attackers send crafted HTTP requests containing traversal sequences (../, encoded variants, absolute paths) to the LaunchServer file-serving endpoint to read files outside the intended web root, including server configs, private keys, and auth databases.

MITRE ATT&CK

Tactic
Initial Access Collection

QRadar Detection Query

IBM QRadar (QRadar)
sql
SELECT sourceip, destinationip, "URL", starttime
FROM events
WHERE "URL" ILIKE '%FileServerHandler%'
AND ("URL" ILIKE '%..%2f%' OR "URL" ILIKE '%..%5c%' OR "URL" ILIKE '%../%' OR "URL" ILIKE '%%2e%2e%2f%' OR "URL" ILIKE '%..%c0%af%')
LAST 24 HOURS
critical severity medium confidence

Detects HTTP requests targeting LaunchServer's FileServerHandler with embedded path traversal sequences consistent with CVE-2026-54617 exploitation.

Data Sources

Web Proxy Flow LogsHTTP Application Logs

Required Tables

events

False Positives & Tuning

  • Legitimate encoded query parameters from launcher clients
  • Authorized security scanning activity
  • Proxy rewrite chains logging pre-decoded URLs

Other platforms for CVE-2026-54617


Testing Methodology

Validate this detection against 3 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.

  1. Test 1Basic path traversal against FileServerHandler

    Expected signal: Web/proxy access log entry showing GET request to FileServerHandler with '../' sequences and response body containing /etc/passwd content or a 200 status.

  2. Test 2URL-encoded traversal against FileServerHandler

    Expected signal: Access log entry with percent-encoded traversal sequences in the request URI/query targeting FileServerHandler.

  3. Test 3Windows-style backslash traversal against FileServerHandler

    Expected signal: IIS/web log entry showing a request to FileServerHandler containing '..%5c' sequences and an unusual response size for win.ini content.

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