Direct paste of the update log / change logs:
SMF 2.0.13 January 4, 2017
=================================================================
! Some file versions didn't get modified in the 2.0.12 patch
! Added check and sanitization for $_REQUEST['u'] in LogInOut.php and Reminder.php
! Added check and sanitization for $_REQUEST['uid'] in Reminder.php
! Properly sanitize author's website for packages
! Added session check when uploading packages
! Added session check when copying template files from one theme to another
! The code to remove empty BBCode was sometimes breaking things (reported by @rjen; fix provided by Sesquipedalian)
! Remove hardcoded limits for safe_unserialize as it was causing cache problems
! Update the cal_max_year setting to 2030
--
Pretty sure i read somewhere in a email that it also helped it fix security issues
SMF 2.0.13 January 4, 2017
=================================================================
! Some file versions didn't get modified in the 2.0.12 patch
! Added check and sanitization for $_REQUEST['u'] in LogInOut.php and Reminder.php
! Added check and sanitization for $_REQUEST['uid'] in Reminder.php
! Properly sanitize author's website for packages
! Added session check when uploading packages
! Added session check when copying template files from one theme to another
! The code to remove empty BBCode was sometimes breaking things (reported by @rjen; fix provided by Sesquipedalian)
! Remove hardcoded limits for safe_unserialize as it was causing cache problems
! Update the cal_max_year setting to 2030
--
Pretty sure i read somewhere in a email that it also helped it fix security issues
