Prepare release.

mnemo/docs/RELEASE_NOTES

@@ -1,11 +1,11 @@
 <?php
 /* Security release? */
-$notes['security'] = false;
+$notes['security'] = true;
 
 /* Mailing list release notes. */
 $notes['changes'] = <<<ML
 The Horde Team is pleased to announce the final release of the Mnemo Note
-Manager version H5 (4.2.2).
+Manager version H5 (4.2.3).
 
 The Mnemo Note Manager is the Horde notes/memos application. It allows users to
 keep web-based notes and freeform text. Notes may be shared with other users
@@ -19,8 +19,12 @@ http://www.horde.org/apps/nag/docs/UPGRADING
 For detailed installation and configuration instructions, please see
 http://www.horde.org/apps/nag/docs/INSTALL
 
-The major changes compared to the Mnemo version H5 (4.2.1) are:
-    * Small bugfixes and improvements.
+The major changes compared to the Mnemo version H5 (4.2.2) are:
+    * Fixed permission check when editing notes. Mitigation: the attacker needs
+      to know the note's (random) URL to exploit this flaw.
+    * Small API improvement.
+
+Thanks to Christopher Neuhaus for reporting the security issue.
 ML;
 
 $notes['name'] = 'Mnemo';