<UL>
    <LI><FONT size=2 face=Verdana>random text<STRONG>random text</STRONG>random text<SPAN style="LINE-HEIGHT: 115%; FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 11pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA"><SPAN style="mso-spacerun: yes">&nbsp;</SPAN>random text</SPAN> </FONT></LI>
    <LI><FONT size=2 face=Verdana><FONT size=2 face=Verdana><STRONG>random text</STRONG></FONT></LI> <LI>random text</FONT></LI>
    <LI><FONT size=2 face=Verdana>random text</FONT></LI>
    <LI><FONT size=2 face=Verdana>random text</FONT></LI>

<UL>
    <LI>random text<STRONG>random text</STRONG>random text<SPAN style="LINE-HEIGHT: 115%; FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 11pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA"><SPAN style="mso-spacerun: yes">&nbsp;</SPAN>random text</SPAN></LI>
    <LI><STRONG>random text</STRONG></LI>
    <LI>random text</LI>
    <LI>random text</LI>
    <LI>random text</LI>

loc.result = rereplace(arguments.htmlString, "\<FONT[^*\>", "", "ALL");

<cfscript>
/** removes the given tag from the input html while keeping its contents */
function removeTag(input, tagname){

    var Jsoup = createObject("java", "org.jsoup.Jsoup");
    var doc   = Jsoup.parse(arguments.input);
    var body  = doc.body().child(0);
    var tags  = body.select(arguments.tagname);

    for (var tag in tags){
        for (var attr in tag.attributes().asList())
            tag.removeAttr(attr.getKey());
    }

    var result = body.toString();
    result = replace(result, "<#arguments.tagname#>",  "", "all");
    result = replace(result, "</#arguments.tagname#>", "", "all");

    return result;
}
</cfscript>

cleanHtml = removeTag(inputHtml, "font");

<cfsavecontent variable="input">
<UL>
    <LI><FONT size=2 face=Verdana>random text 1<STRONG>random text 2</STRONG>random text 3<SPAN style="LINE-HEIGHT: 115%; FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 11pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA"><SPAN style="mso-spacerun: yes">&nbsp;</SPAN>random text 4</SPAN> </FONT></LI>
    <LI><FONT size=2 face=Verdana><FONT size=2 face=Verdana><STRONG>random text 5</STRONG></FONT></LI> <LI>random text 5</FONT></LI>
    <LI><FONT size=2 face=Verdana>random text 6</FONT></LI>
    <LI><FONT size=2 face=Verdana>random text 7</FONT></LI>
</cfsavecontent>

<cfdump var="#{ output: removeTag(input, "font"), input: input }#">