---
id: CVE-2026-15726
title: >-
  The Serious Slider plugin for WordPress is vulnerable to Stored Cross-Site
  Scripting via 'theme' Shortcode Attribute in all versions up to, and
  including, 1.4.0 due to insufficient input sanitization and output escaping
summary: >-
  The Serious Slider plugin for WordPress is vulnerable to Stored Cross-Site
  Scripting via 'theme' Shortcode Attribute in all versions up to, and
  including, 1.4.0 due to insufficient input sanitization and output escaping.
  This makes it po…
severity: medium
cvss: 6.4
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N'
cwe:
  - CWE-79
published: '2026-08-16'
updated: '2026-08-16'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-15726'
references:
  - url: >-
      https://plugins.trac.wordpress.org/browser/cryout-serious-slider/tags/1.4.0/inc/shortcodes.php#L102
    label: security@wordfence.com
  - url: >-
      https://plugins.trac.wordpress.org/browser/cryout-serious-slider/tags/1.4.0/inc/shortcodes.php#L111
    label: security@wordfence.com
  - url: >-
      https://plugins.trac.wordpress.org/browser/cryout-serious-slider/tags/1.4.0/inc/shortcodes.php#L244
    label: security@wordfence.com
  - url: >-
      https://plugins.trac.wordpress.org/browser/cryout-serious-slider/tags/1.4.0/inc/shortcodes.php#L55
    label: security@wordfence.com
  - url: >-
      https://plugins.trac.wordpress.org/changeset?reponame=&old=3640247%40cryout-serious-slider&new=3640247%40cryout-serious-slider
    label: security@wordfence.com
  - url: >-
      https://www.wordfence.com/threat-intel/vulnerabilities/id/c8f45054-e6a4-403b-94eb-2dd2a4840c22?source=cve
    label: security@wordfence.com
tags:
  - nvd
ingestedAt: '2026-08-16T13:39:06.956Z'
epss: 0.00349
epssPercentile: 0.25725
---

## Overview

The Serious Slider plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'theme' Shortcode Attribute in all versions up to, and including, 1.4.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.