Critical Patch Update April 2005 question

In reviewing everything covered by the April 2005 Critical Patch update it looks like most of it doesn't apply to my databases. The one that I'm not clear on is DB05 where the component is listed as Authentication with SQL (Oracle Net) listed as the Access required.

Does anyone have any details on this vulnerability? I'm not clear on what the "Authentication" component signifies. And of course searching Metalink on Authentication turned up 100s of unrelated links.

Thanks,
Jay Miller

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