CVE-2026-19760
The WP Fastest Cache – WordPress Cache Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via HTTP Host Header in all versions up to, and including, 1.5.0 due to insufficient input sanitization and output escaping.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.40%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
The WP Fastest Cache – WordPress Cache Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via HTTP Host Header in all versions up to, and including, 1.5.0 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 requires the Polylang or Polylang Pro plugin to be active and the Combine JS option to be enabled, as these conditions trigger the vulnerable Host-header-to-URL code path that writes attacker-controlled script src values into the shared page-cache file served to all subsequent visitors.
- CVSS 3.1
- 7.2 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- EPSS
- 0.40% probability · 34th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Source
- security@wordfence.com
References
- https://plugins.trac.wordpress.org/browser/wp-fastest-cache/tags/1.4.9/inc/js-utilities.php#L257
- https://plugins.trac.wordpress.org/browser/wp-fastest-cache/tags/1.4.9/inc/js-utilities.php#L274
- https://plugins.trac.wordpress.org/browser/wp-fastest-cache/tags/1.4.9/wpFastestCache.php#L507
- https://plugins.trac.wordpress.org/browser/wp-fastest-cache/tags/1.5.0/inc/js-utilities.php#L257
- https://plugins.trac.wordpress.org/browser/wp-fastest-cache/tags/1.5.0/inc/js-utilities.php#L274
- https://plugins.trac.wordpress.org/browser/wp-fastest-cache/tags/1.5.0/wpFastestCache.php#L507
- https://www.wordfence.com/threat-intel/vulnerabilities/id/69a22238-88e8-4ff5-8e2b-8c58a04ff154?source=cve
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.