brainstormforce Astra Plugin up to 4.12.3 on WordPress astra_get_responsive_background_obj cross site scripting

Summaryinfo

A vulnerability was found in brainstormforce Astra Plugin up to 4.12.3 on WordPress. It has been declared as problematic. The affected element is the function astra_get_responsive_background_obj. Executing a manipulation of the argument ast-page-background-meta/ast-content-background-meta can lead to cross site scripting. This vulnerability is handled as CVE-2026-3534. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability has been found in brainstormforce Astra Plugin up to 4.12.3 on WordPress and classified as problematic. This vulnerability affects the function astra_get_responsive_background_obj. The manipulation of the argument ast-page-background-meta/ast-content-background-meta with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. CVE summarizes:

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.

The weakness was released by Alex Hickey. The advisory is shared for download at wordfence.com. This vulnerability was named CVE-2026-3534 since 03/04/2026. The exploitation appears to be easy. The attack can be initiated remotely. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.007.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• WordPress Plugin

Vendor

• brainstormforce

Name

• Astra Plugin

Version

• 4.12.0
• 4.12.1
• 4.12.2
• 4.12.3

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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