CVE-2020-28039: Canonical Ubuntu Linux

Critical severity, CVSS 9.1. EPSS: 4.1% chance of exploitation in the next 30 days.

is_protected_meta in wp-includes/meta.php in WordPress before 5.5.2 allows arbitrary file deletion because it does not properly determine whether a meta key is considered protected.

Affected products

• Canonical Ubuntu Linux: version 16.04 only; version 18.04 only; version 20.04 only
• Debian Debian Linux: version 9.0 only; version 10.0 only
• WordPress WordPress: before 5.5.2 (fixed in 5.5.2)

Published 2020-11-02. Last modified 2026-06-17.