CVE-2021-29447: Debian Linux

Medium severity, CVSS 6.5. EPSS: 85.7% chance of exploitation in the next 30 days.

Wordpress is an open source CMS. A user with the ability to upload files (like an Author) can exploit an XML parsing issue in the Media Library leading to XXE attacks. This requires WordPress installation to be using PHP 8. Access to internal files is possible in a successful XXE attack. This has been patched in WordPress version 5.7.1, along with the older affected versions via a minor release. We strongly recommend you keep auto-updates enabled.

Affected products

• Debian Debian Linux: version 9.0 only; version 10.0 only
• WordPress WordPress: from 5.6.0, before 5.7.1 (fixed in 5.7.1)

Published 2021-04-15. Last modified 2026-06-17.