CVE-2026-3534: Brainstormforce Astra

Medium severity, CVSS 6.4. EPSS: 0.4% chance of exploitation in the next 30 days.

The Astra theme for WordPress is vulnerable to Stored Cross-Site Scripting via the `ast-page-background-meta` and `ast-content-background-meta` post meta fields in all versions up to, and including, 4.12.3. This is due to insufficient input sanitization on meta registration and missing output escaping in the `astra_get_responsive_background_obj()` function for four CSS-context sub-properties (`background-color`, `background-image`, `overlay-color`, `overlay-gradient`). This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Affected products

• Brainstormforce Astra: up to and including 4.12.3

Published 2026-03-11. Last modified 2026-06-17.