Wordpress editor "forgets" everything after </textarea>

[Nosve]

I have two pages, 'Content' and 'Feedback', on the Wordpress-based site redesign I'm working on ( http://www.genocideintervention.net/testdrive/wordpress) that have forms on them. Most of the form's inputs (text and textarea types) appear just fine. However, there is a bug regarding the 'submit' button of either form. As soon as I add the button to the page code and save, it appears on the site just fine. If I ever go back to the page editor and edit the page further, however, it's as if the site forgets the button ever existed. The submit button disappears from the page, along with the <tr> and <td> that it was contained in. Even more strangely, the submit button isn't even really gone--it appears in the page editor window, right below the page content text box, as you can see in the attached screencap. It has just disappeared from the code and the site.

I know the form works--I've tested it during the times immediately proceeding my adding the submit button code. But having to rewrite my submit <td> after every tweak is driving me mad! And while I don't know if this bug could have malicious applications, having page code apparently executing within the editor can't be a good thing...

Submit button no longer appearing in the code but appearing below the text box in the editor window

The form code that this happening with:

<form action="http://www.genocideintervention.net/testdrive/wordpress/feedbackcode.php" method="post">
<table summary="feedback form" border="0" cellpadding="5" cellspacing="5">
<tr>
<td><label for="name">Name:</label></td>
<td><input name="name" size="25" class="contact" type="text" /></td>
</tr>
<tr>
<td><label for="email">Email address:</label></td>
<td><input name="email" size="25" class="contact" type="text" /></td>
</tr>
<tr>
<td><label for="official">Who you called:</label></td>
<td><input name="official" size="25" class="contact" type="text" /></td>
</tr>
<tr>
<td colspan="2"><label for="comments">Comments:</label><textarea rows="15" cols="45" name="comments" class="contact"></textarea></td>
</tr>
<!-- this is the part that disappears -->
<tr>
<td colspan="2">
<input type="submit" value="Send Feedback" /><br />
</td>
</tr>
<!-- /disappear -->
</table>
</form>

Turn off the visual editor entirely. Does it still happen then?

It's not the buttons that "dissapear".

It's everything after the </textarea>, because that's being interpreted as the end of the editors textarea.

Nazgul appears to be right. Once I took out the textarea, the 'submit' button appeared just fine.

That the page interprets an entered </textarea> as the end of the editor is bad, though. I'll put up a screencap in a second, but this bug also makes it so you can enter unescaped PHP into the page editor. Seems like a security risk to me.

Wouldn't it only be a security risk if it actually executed it?

I can type PHP code on this page right now and it's not a security problem...

It's not a security risk.

You need the unfiltered_html capability to include javascript/raw php in your pages/posts, which by default is only given to administrators.

Contributers don't have that capability and therefore can't abuse it, because script tags and the like are filtered out.

Strike that, you're right. It appeared that it wasn't escaping the post-<textarea> PHP code but now it seems that that was because I was testing with echo() instead of something more interesting.

So this bug is simply a headache for anyone who wants to have forms on their blog. :)

Uncommon usage. Maybe a shortcode for textarea?

Duplicate of #6449.