XSS in Stepasyuk Filter Everything — WordPress & Woocommerce Filters

CVE-2026-87869

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.

Vulnerability class: XSS (Cross-Site Scripting)

Published .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-87869?
CVE-2026-87869 is a medium-severity vulnerability in Stepasyuk Filter Everything — WordPress & Woocommerce Filters, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-10-10.
How severe is CVE-2026-87869?
Medium severity. CVSS v3 base score is 6.1 out of 10.