2 files changed, 12 insertions, 1 deletions
diff --git a/phpBB/phpbb/textformatter/s9e/factory.php b/phpBB/phpbb/textformatter/s9e/factory.php
index 6191b9a315..dca1c78d40 100644
--- a/phpBB/phpbb/textformatter/s9e/factory.php
+++ b/phpBB/phpbb/textformatter/s9e/factory.php
@@ -110,7 +110,7 @@ class factory implements \phpbb\textformatter\cache_interface
 		'i'     => '<span style="font-style: italic"><xsl:apply-templates/></span>',
 		'u'     => '<span style="text-decoration: underline"><xsl:apply-templates/></span>',
 		'img'   => '<img src="{IMAGEURL}" class="postimage" alt="{L_IMAGE}"/>',
-		'size'  => '<span style="font-size: {FONTSIZE}%; line-height: normal"><xsl:apply-templates/></span>',
+		'size'	=> '<span><xsl:attribute name="style"><xsl:text>font-size: </xsl:text><xsl:value-of select="substring(@size, 1, 4)"/><xsl:text>%; line-height: normal</xsl:text></xsl:attribute><xsl:apply-templates/></span>',
 		'color' => '<span style="color: {COLOR}"><xsl:apply-templates/></span>',
 		'email' => '<a>
 			<xsl:attribute name="href">
diff --git a/phpBB/phpbb/textformatter/s9e/parser.php b/phpBB/phpbb/textformatter/s9e/parser.php
index 3698dca224..1bc56a8cb4 100644
--- a/phpBB/phpbb/textformatter/s9e/parser.php
+++ b/phpBB/phpbb/textformatter/s9e/parser.php
@@ -228,6 +228,10 @@ class parser implements \phpbb\textformatter\parser_interface
 			{
 				$errors[] = array($msg);
 			}
+			else if ($msg === 'INVALID_FONT_SIZE')
+			{
+				$errors[] = [$msg, $context['invalid_size']];
+			}
 		}
 
 		// Deduplicate error messages. array_unique() only works on strings so we have to serialize
@@ -335,6 +339,13 @@ class parser implements \phpbb\textformatter\parser_interface
 	*/
 	static public function filter_font_size($size, $max_size, Logger $logger)
 	{
+		if (!is_numeric($size))
+		{
+			$logger->err('INVALID_FONT_SIZE', ['invalid_size' => htmlspecialchars($size)]);
+
+			return false;
+		}
+
 		if ($max_size && $size > $max_size)
 		{
 			$logger->err('MAX_FONT_SIZE_EXCEEDED', array('max_size' => $max_size));