WordPress 4.9.1 is now available. This is a security and maintenance release for all versions since WordPress 3.7. We strongly encourage you to update your sites immediately.
WordPress versions 4.9 and earlier are affected by four security issues which could potentially be exploited as part of a multi-vector attack. As part of the core team’s ongoing commitment to security hardening, the following fixes have been implemented in 4.9.1:
- Use a properly generated hash for the
newbloguserkey instead of a determinate substring.
- Add escaping to the language attributes used on
- Ensure the attributes of enclosures are correctly escaped in RSS and Atom feeds.
Thank you to the reporters of these issues for practicing responsible security disclosure: Rahul Pratap Singh and John Blackbourn.
Eleven other bugs were fixed in WordPress 4.9.1. Particularly of note were:
- Issues relating to the caching of theme template files.
- The inability to edit theme and plugin files on Windows based servers.
Download WordPress 4.9.1 or venture over to Dashboard → Updates and click “Update Now.” Sites that support automatic background updates are already beginning to update automatically.