CVE-2026-107764: SiteOrigin CSS DOM-based cross-site scripting (XSS) vulnerability
high 7.2 published 2026-10-16
- Affected versions
- 1.6.7 and older
- Fixed in
- 1.6.8 *
- Latest version
- 1.6.8
- Severity
- High · CVSS 7.2
- Active installs
- 100,000+
- Type
- DOM-based cross-site scripting (XSS)
* The source does not name a fixed version; this is the first wordpress.org release after the last affected version.
What an attacker needs
- Access: None. No account or login is needed.
CVSS vector (score by Wordfence): CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
What to do now
- Update SiteOrigin CSS to 1.6.8 or newer: Dashboard → Updates, or Plugins → “update now”.
- If you cannot update right away, deactivate it until you can.
- Turn on auto-updates for it: Plugins → “Enable auto-updates” on its row.
- Not sure which version you run? Check your version against every known SiteOrigin CSS issue.
With WP-CLI:
wp plugin get so-css --field=version. - If you ran an affected version and something looks off (new admin users, spam pages, redirects), run the free scan below.
The advisory
The SiteOrigin CSS plugin for WordPress is vulnerable to Stored DOM-Based Cross-Site Scripting via the 'url (comment_author_url)' parameter in all versions up to, and including, 1.6.7 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is possible because WordPress core's esc_url() preserves HTML entity-encoded characters, allowing a crafted entity-encoded payload in the comment 'Website' field to survive storage and be DOM-decoded by the browser into executable markup at the sink.
References
- NVD CVE-2026-107764 nvd.nist.gov
- Wordfence advisory www.wordfence.com
- github.com github.com
- Plugin source plugins.trac.wordpress.org
Related
Ran an affected version? Check your site for signs of a hack
The free scan reads the public side of your site and looks for spam pages, hidden redirects, injected scripts and blacklist entries. No login, no install, about a minute.
Where this data comes from
- CVE record, score and references: NIST National Vulnerability Database (NVD), checked 2026-11-04. This product uses data from the NVD API but is not endorsed or certified by the NVD.
- Versions and install counts: wordpress.org/plugins/so-css (Plugins API), fetched 2026-11-04.
- The summary, “what an attacker needs” and “what to do” sections are our plain-English reading of the record and the plugin's release history; the quoted description is the record's own text. Spot an error? Email Daniel.