diff --git a/ChangeLog b/ChangeLog
index d30aa3417ad6..31d89761de41 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2017-11-10  Carlos Garcia Campos  <cgarcia@igalia.com>
+
+        Unreviewed. Update OptionsGTK.cmake and NEWS for 2.18.3 release.
+
+        * Source/cmake/OptionsGTK.cmake: Bump version numbers.
+
 2017-10-27  Carlos Garcia Campos  <cgarcia@igalia.com>
 
         Unreviewed. Update OptionsGTK.cmake and NEWS for 2.18.2 release.
diff --git a/Source/WebKit/ChangeLog b/Source/WebKit/ChangeLog
index 4b45c3e65363..b950a50fc806 100644
--- a/Source/WebKit/ChangeLog
+++ b/Source/WebKit/ChangeLog
@@ -1,3 +1,9 @@
+2017-11-10  Carlos Garcia Campos  <cgarcia@igalia.com>
+
+        Unreviewed. Update OptionsGTK.cmake and NEWS for 2.18.3 release.
+
+        * gtk/NEWS: Add release notes for 2.18.3.
+
 2017-10-27  Carlos Garcia Campos  <cgarcia@igalia.com>
 
         Unreviewed. Update OptionsGTK.cmake and NEWS for 2.18.2 release.
diff --git a/Source/WebKit/gtk/NEWS b/Source/WebKit/gtk/NEWS
index 7ef381990b54..1743624f3a39 100644
--- a/Source/WebKit/gtk/NEWS
+++ b/Source/WebKit/gtk/NEWS
@@ -1,3 +1,13 @@
+==================
+WebKitGTK+  2.18.3
+==================
+
+What's new in WebKitGTK+ 2.18.3?
+
+  - Improve calculation of font metrics to prevent scrollbars from being shown unnecessarily in some cases.
+  - Fix handling of null capabilities in WebDriver implementation.
+  - Security fixes: CVE-2017-13798, CVE-2017-13788, CVE-2017-13803.
+
 ==================
 WebKitGTK+  2.18.2
 ==================
diff --git a/Source/cmake/OptionsGTK.cmake b/Source/cmake/OptionsGTK.cmake
index 39ca055d94ab..0148e5b77195 100644
--- a/Source/cmake/OptionsGTK.cmake
+++ b/Source/cmake/OptionsGTK.cmake
@@ -1,11 +1,11 @@
 include(GNUInstallDirs)
 include(VersioningUtils)
 
-SET_PROJECT_VERSION(2 18 2)
+SET_PROJECT_VERSION(2 18 3)
 set(WEBKITGTK_API_VERSION 4.0)
 
-CALCULATE_LIBRARY_VERSIONS_FROM_LIBTOOL_TRIPLE(WEBKIT2 61 5 24)
-CALCULATE_LIBRARY_VERSIONS_FROM_LIBTOOL_TRIPLE(JAVASCRIPTCORE 24 11 6)
+CALCULATE_LIBRARY_VERSIONS_FROM_LIBTOOL_TRIPLE(WEBKIT2 61 6 24)
+CALCULATE_LIBRARY_VERSIONS_FROM_LIBTOOL_TRIPLE(JAVASCRIPTCORE 24 12 6)
 
 # These are shared variables, but we special case their definition so that we can use the
 # CMAKE_INSTALL_* variables that are populated by the GNUInstallDirs macro.