CVE-2026-87869: Filter Everything reflected cross-site scripting (XSS) vulnerability
medium 6.1 published 2026-10-10 · updated 2026-10-13
- Affected versions
- 1.9.6 and older
- Fixed in
- 1.9.7 *
- Latest version
- 1.9.8
- Severity
- Medium · CVSS 6.1
- Active installs
- 50,000+
- Type
- Reflected 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.
- Interaction: It also needs someone on the site (often an admin) to click a link, open a page or submit a form the attacker prepared.
CVSS vector (score by Wordfence): CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
What to do now
- Update Filter Everything to 1.9.7 or newer (the latest is 1.9.8): 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 Filter Everything issue.
With WP-CLI:
wp plugin get filter-everything --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 Filter Everything — WordPress & WooCommerce Filters plugin for WordPress is vulnerable to Reflected Cross-Site Scripting in versions up to, and including, 1.9.6. This is due to insufficient input sanitization and output escaping in the flrt_elementor_load_more_anchor() function. The function reads query parameters from $_SERVER['REQUEST_URI'] via getFormActionOrFullPageUrl(true), which URL-decodes them through parse_str() and re-assembles them using build_query() — a WordPress core function that does NOT re-encode values ($urlencode=false). The resulting URL, containing unescaped special characters, is injected into a data-next-page HTML attribute via preg_replace() without esc_attr() or esc_url(). This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a specially crafted link.
References
- NVD CVE-2026-87869 nvd.nist.gov
- Wordfence advisory www.wordfence.com
- Code change (fix) plugins.trac.wordpress.org
- 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/filter-everything (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.