Subject Matter Jurisdiction was procured by fraud.
A truly void judgment can always be set aside; you need to first file in the trial court a motion to vacate the judgment; if that is denied, you can appeal from that order. Whether you can now appeal directly from the judgment depends on when the judgment was entered and other factors.
That being said, a truly void judgment is a rarity. You have to convince the judge that it was procured by "extrinsic" fraud rather than "intrinsic" fraud, the definitions of which are too complicated to explain here. As you provide no specific details of the "fraud" (I do not know what you mean by "procuring subject matter jurisdiction") it is impossible to provide further advice.
You should, of course, retain counsel to assist you in this.
Nothing contained in this communication is intended to be, or shall be deemed as, legal advice, counsel, or services to on or behalf of any person or any entity. Usage of the Avvo website is not intended to and shall not create any obligation or relationship between the user and the Law Office of Herb Fox, including but not limited to, an attorney-client relationship. Further, the communications on this website between you and the Law Office of Herb Fox may not be privileged or confidential. Finally, your situation may be governed by deadlines that may or may not have already lapsed, and you may lose your rights if you do or did not act within those deadlines.
Criminal Defense Attorney
You should speak with an attorney and have your "evidence" supporting documents etc in hand. This is not a simple proposition and not something a lay person should undertake without the assistance of counsel
The above is not intended as legal advice. The response does not constitute the creation of an attorney client relationship as this forum does not provide for a confidential communication.