In a paper titled "Variations in exploit methods between Linux and Windows" presented at Blackhat 2003, David Litchfield has illustrated multiple vulnerabilities in the Oracle 9i XML Database (XDB). Successful exploits may allow remote attackers to run arbitrary code in the security context of the vulnerable service.
Block external access at the network boundary, unless external parties require service.
If applicable, filter traffic at the network perimeter. Allow traffic destined for the affected server from trusted hosts and networks only. Deny all other communications. Filter traffic to ports 8080 and 2100.
Deploy network intrusion detection systems to monitor network traffic for malicious activity.
NIDS will help detect malicious traffic, build effective firewall rules, and prevent further attacks on vulnerable applications.
Implement multiple redundant layers of security.
Various memory-protection schemes (such as nonexecutable and randomly mapped memory segments) may hinder an attacker's ability to exploit this vulnerability to execute arbitrary code.
Disable any services that are not needed.
This vulnerability is remotely exploitable through services enabled by default. Disabling such services may close future channels of attack.
Oracle has released patches to address these issues. See the referenced advisory (Oracle Security Alert 58) for details on obtaining and applying patches using the Oracle metalink site tool.