diff --git a/libpng-1.6.20.tar.xz b/libpng-1.6.20.tar.xz
deleted file mode 100644
index 813d390..0000000
--- a/libpng-1.6.20.tar.xz
+++ /dev/null
@@ -1,3 +0,0 @@
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-size 942672
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deleted file mode 100644
index c989cff..0000000
--- a/libpng-1.6.20.tar.xz.asc
+++ /dev/null
@@ -1,17 +0,0 @@
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diff --git a/libpng-1.6.21.tar.xz b/libpng-1.6.21.tar.xz
new file mode 100644
index 0000000..bf33774
--- /dev/null
+++ b/libpng-1.6.21.tar.xz
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:6c8f1849eb9264219bf5d703601e5abe92a58651ecae927a03d1a1aa15ee2083
+size 943980
diff --git a/libpng-1.6.21.tar.xz.asc b/libpng-1.6.21.tar.xz.asc
new file mode 100644
index 0000000..4ae8fc6
--- /dev/null
+++ b/libpng-1.6.21.tar.xz.asc
@@ -0,0 +1,17 @@
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diff --git a/libpng16.changes b/libpng16.changes
index a861dc6..f88e7ed 100644
--- a/libpng16.changes
+++ b/libpng16.changes
@@ -1,3 +1,16 @@
+-------------------------------------------------------------------
+Sun Jan 17 14:10:43 UTC 2016 - jengelh@inai.de
+
+- Update to new upstream release 1.6.21
+* Widened the 'limit' check on the internally calculated error limits in
+  the 'DIGITIZE' case (the code used prior to 1.7 for rgb_to_gray error
+  checks) and changed the check to only operate in non-release builds
+  (base build type not RC or RELEASE.)
+* Fixed undefined behavior in pngvalid.c, undefined because
+  (png_byte) << shift is undefined if it changes the signed bit
+  (because png_byte is promoted to int). The libpng exported functions
+  png_get_uint_32 and png_get_uint_16 handle this.
+
 -------------------------------------------------------------------
 Thu Dec  3 15:11:03 UTC 2015 - pgajdos@suse.com
 
diff --git a/libpng16.spec b/libpng16.spec
index bff3526..6082963 100644
--- a/libpng16.spec
+++ b/libpng16.spec
@@ -1,7 +1,7 @@
 #
 # spec file for package libpng16
 #
-# Copyright (c) 2015 SUSE LINUX GmbH, Nuernberg, Germany.
+# Copyright (c) 2016 SUSE LINUX GmbH, Nuernberg, Germany.
 #
 # All modifications and additions to the file contributed by third parties
 # remain the property of their copyright owners, unless otherwise agreed
@@ -19,7 +19,7 @@
 #
 %define major   1
 %define minor   6
-%define micro   20
+%define micro   21
 %define branch  %{major}%{minor}
 %define libname libpng%{branch}-%{branch}
 
@@ -43,7 +43,6 @@ BuildRoot:      %{_tmppath}/%{name}-%{version}-build
 %define debug_package_requires %{libname} = %{version}-%{release}
 
 %package -n %{libname}
-
 Summary:        Library for the Portable Network Graphics Format (PNG)
 Group:          System/Libraries
 # bug437293