XSS in Brainstormforce Astra
CVE-2026-3534
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.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.002 (10.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.
Affected products
- Brainstormforce Astra — versions 0
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-3534?
- CVE-2026-3534 is a medium-severity vulnerability in Brainstormforce Astra, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-03-11.
- How severe is CVE-2026-3534?
- Medium severity. CVSS v3 base score is 6.4 out of 10.