What is the CVSS score of CVE-2026-15726?

CVE-2026-15726 has a CVSS 3.1 base score of 6.4 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N. EPSS exploitation probability: 0.2%.

Serious Slider CVE-2026-15726

EUVD-2026-59867 MEDIUM

Cross-site Scripting (XSS) (CWE-79)

2026-08-16 Wordfence

GHSA-8x7q-3q4v-jcjq

WordPress XSS Wordpress Plugin Serious Slider

6.4

CVSS 3.1 · Vendor: Wordfence

Severity by source

Vendor (Wordfence) PRIMARY

6.4 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

vuln.today AI

6.4 MEDIUM

Contributor account required for injection (PR:L); stored XSS executes in victim browsers, changing scope (S:C); no server-side availability impact warrants A:N.

3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

4.0 AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

Primary rating from Vendor (Wordfence).

CVSS VectorVendor: Wordfence

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

Analysis Generated

Aug 16, 2026 - 05:12 vuln.today

CVE Published

Aug 16, 2026 - 04:24 cve.org

MEDIUM 6.4

DescriptionCVE.org

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.

AnalysisAI

Stored Cross-Site Scripting in the Serious Slider WordPress plugin (all versions up to and including 1.4.0) allows authenticated contributors to inject persistent malicious scripts via the 'theme' shortcode attribute, which then execute in the browser of any user who subsequently visits the affected page. The flaw originates from insufficient sanitization and output escaping in multiple code paths within inc/shortcodes.php, as confirmed by Wordfence and EUVD-2026-59867. No public exploit has been identified at time of analysis, and the vulnerability is not listed in CISA KEV.

Technical ContextAI

The affected code is in the Serious Slider plugin (CPE: cpe:2.3:a:cryout-creations:serious_slider:*:*:*:*:*:*:*:*) developed by Cryout Creations for WordPress. The vulnerable logic is distributed across at least four locations in inc/shortcodes.php (lines 55, 102, 111, and 244), where the 'theme' attribute of the plugin's shortcode is reflected into the HTML output without proper encoding. CWE-79 (Improper Neutralization of Input During Web Page Generation - Cross-Site Scripting) identifies the root cause: user-supplied shortcode attribute values reach the rendered page without escaping, enabling injected scripts to execute in the context of any visitor's browser. WordPress shortcode parameters are intended for presentation logic but must be sanitized before output; the absence of that sanitization here allows the attribute to serve as a persistent script injection vector.

RemediationAI

Update the Serious Slider plugin to a version beyond 1.4.0; the upstream fix is reflected in the WordPress plugin repository changeset at https://plugins.trac.wordpress.org/changeset?reponame=&old=3640247%40cryout-serious-slider&new=3640247%40cryout-serious-slider, though the exact patched release version tag was not independently confirmed from the available data - verify the current version in the WordPress plugin directory before deploying. As an interim compensating control, restrict contributor-level account creation to verified trusted users and audit all existing contributor accounts for unauthorized or compromised access; this eliminates the PR:L entry point and makes exploitation infeasible without also compromising a higher-privilege account. If slider functionality is not actively required, deactivating or uninstalling the plugin entirely removes the attack surface with no security trade-offs beyond loss of slider rendering. The Wordfence advisory at https://www.wordfence.com/threat-intel/vulnerabilities/id/c8f45054-e6a4-403b-94eb-2dd2a4840c22 should be monitored for patch version confirmation.