I've tried this on a number of Movable Type 3.2 blogs out there, and it doesn't happen on theirs, but when you pass a badly formed query string to a CGI script, such as the query string in the Select a Design using StyleCatcher link at the bottom of the Templates page, extlib/CGI.pm croaks with the error:
Use of uninitialized value in hash element at /mt/extlib/CGI.pm line 554
That's if you're lucky and you're debugging with cgiwrapd. Otherwise you will probably just get an HTTP 500 Internal Server Error.
The offending link looks like this:
/mt/plugins/StyleCatcher/stylecatcher.cgi?;from=list_templates;blog_id=1
But I was also able to make mt.cgi die by just passing it
/mt/mt.cgi?;foo
Here's a patch which fixes the problem for me.
--- MT-3.2-en_US/extlib/CGI.pm Wed Oct 12 08:55:56 2005
+++ mt/extlib/CGI.pm Tue Jul 11 19:18:56 2006
@@ -546,6 +546,7 @@
my($param,$value);
foreach (@pairs) {
($param,$value) = split('=',$_,2);
+ next if not defined $param;
next if $NO_UNDEF_PARAMS and not defined $value;
$value = '' unless defined $value;
$param = unescape($param);