From 55bee6cdccae3a83200c799a23a4fda4d135717f Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Thu, 1 Sep 2016 20:57:51 +0300
Subject: [PATCH] Only unescape correct UTF8 sequences in MediaWiki page
 sections

---
 Bugzilla/Template.pm | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/Bugzilla/Template.pm b/Bugzilla/Template.pm
index 5911785d3..7a095e2e2 100644
--- a/Bugzilla/Template.pm
+++ b/Bugzilla/Template.pm
@@ -422,9 +422,15 @@ sub unquote_wiki_url
         my $anchor = '';
         if ($article =~ s/#(.*)$//so)
         {
+            my $a;
             $anchor = $1;
-            # decode MediaWiki page section name
-            $anchor =~ tr/./%/;
+            # decode MediaWiki page section name (only correct UTF8 sequences)
+            $anchor =~ s/(
+                \.[0-7][A-F0-9]|
+                \.[CD][A-F0-9]\.[89AB][A-F0-9]|
+                \.E[A-F0-9](?:\.[89AB][A-F0-9]){2}|
+                \.F[0-7](?:\.[89AB][A-F0-9]){3}
+            )/($a = $1), ($a =~ tr!.!\%!), ($a)/gesx;
             $anchor = url_decode($anchor);
             $anchor =~ tr/_/ /;
         }