On March 6, 2017, WordPress 4.5.7 was released to the public.
To download WordPress 4.5.7, update automatically from the Dashboard > Updates menu in your site's admin area or visit https://wordpress.org/download/release-archive/.
For step-by-step instructions on installing and updating WordPress:
If you are new to WordPress, we recommend that you begin with the following:
From the WordPress 4.7.3 release post: WordPress versions 4.7.2 and earlier are affected by six security issues:
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