This is how you might do it with HTML::TreeBuilder::XPath: 
use Data::Dumper;
use HTML::TreeBuilder::XPath;

my $html = q|
<ul><li>The following Host Names were requested from a host database:<
+/li>
<ul>
<li>192.5.5.241</li>
<li>192.5.5.242</li>
</ul></ul>
|;

my $tree = HTML::TreeBuilder::XPath->new;
$tree->parse($html);
$tree->eof;

my @wanted;

my @nodes = $tree->findnodes('//ul');
for my $node ( @nodes ) {
    my $text = $node->findvalue('li') or next;
    $text =~ m/^The following Host Name/ or next;
    @wanted = $node->findvalues('ul/li');
    last;
}
print Dumper \@wanted;

[download]
Output: 
$VAR1 = [
          '192.5.5.241',
          '192.5.5.242'
        ];

[download]

In reply to Re: question about lookaheads and threatexpert/html parsing by tangent
in thread question about lookaheads and threatexpert/html parsing by ejc1

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