# Otter Blocks <= 3.2.7 - Authenticated (Contributor+) Stored Cross-Site Scripting via Atomic Wind CSS

- **ID:** WPSEC-2026-1359
- **Plugin:** Otter Blocks – Gutenberg Blocks, Page Builder for Gutenberg Editor & FSE (`otter-blocks`), https://wordpress.org/plugins/otter-blocks/
- **Affected versions:** from 3.1.6 before 3.2.8
- **Fixed in:** 3.2.8 (Update to 3.2.8 or later.)
- **Severity:** Medium 6.4 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N)
- **Weakness:** CWE-79
- **Usage among sites WPSec scans:** plugin Medium, affected versions Medium (as of 2026-10-21)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/otter-blocks
- **Fix released:** 2026-10-19
- **Published:** 2026-10-21
- **URL:** https://wpsec.com/vuln/WPSEC-2026-1359/

## Description

The Otter Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Atomic Wind CSS in versions from 3.1.6 up to, and including, 3.2.7. Generated Atomic Wind stylesheet text, saved through the plugin's style REST route and later printed inside an inline <style> element, was not fully neutralized against a closing style tag, so a crafted value could terminate the <style> element early. This makes it possible for authenticated attackers with contributor-level access and above to inject arbitrary web scripts that execute whenever a user accesses an affected page.

## References

- https://wpsec.com/vuln/WPSEC-2026-1359/
- https://plugins.svn.wordpress.org/otter-blocks/tags/3.2.8/
- https://wordpress.org/plugins/otter-blocks/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-1359/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.