WordPress released version 5.0.1 that fixes seven vulnerabilities.
“We strongly encourage you to update your sites immediately,” WordPress noted in the security release on Thursday morning.
A summary of the bugs discovered by multiple security researchers and addressed in 5.0.1 include:
- Authors could alter meta data to delete files that they weren’t authorized to.
- Authors could create posts of unauthorized post types with specially crafted input.
- Contributors could craft meta data in a way that resulted in PHP object injection.
- Contributors could edit new comments from higher-privileged users, potentially leading to a cross-site scripting vulnerability.
- Specially crafted URL inputs could lead to a cross-site scripting vulnerability in some circumstances. WordPress itself was not affected, but plugins could be in some situations.
- The user activation screen could be indexed by search engines in some uncommon configurations, leading to exposure of email addresses, and in some rare cases, default generated passwords.
- Authors on Apache-hosted sites could upload specifically crafted files that bypass MIME verification, leading to a cross-site scripting vulnerability.
Of note, the WordPress 5.0.1 update now includes support for stronger MIME validation for uploaded files. WordPress versions 5.0 and earlier are affected by the previously listed bugs.