Mixed Media Gallery Blocks <= 3.3.3.1 - Authenticated (Author+) Stored Cross-Site Scripting via sliderMaxHeight Block Attribute
Summary
| CVE | CVE-2026-5743 |
|---|---|
| State | PUBLISHED |
| Assigner | Wordfence |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-11 04:17:23 UTC |
| Updated | 2026-07-11 04:17:23 UTC |
| Description | The SimpLy Gallery Block & Lightbox plugin for WordPress is vulnerable to Stored Cross-Site Scripting via block attributes in all versions up to, and including, 3.3.3.2. This is due to insufficient input sanitization and output escaping on the sliderMaxHeight block attribute in the pgc_sgb_render_callback() function. The vulnerability exists because the pgc_sgb_sanitize_custom_css() function uses a flawed regex pattern that only removes event handlers with quoted values (e.g., onfocus="alert()") but fails to catch unquoted event handlers (e.g., onfocus=alert(document.cookie)), allowing the malicious code to bypass sanitization. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts in pages via block attributes that will execute whenever a user accesses an injected page. |
Risk And Classification
Primary CVSS: v3.1 6.4 MEDIUM from [email protected]
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Problem Types: CWE-79 | CWE-79 CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 6.4 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N |
| 3.1 | CNA | DECLARED | 6.4 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
ChangedConfidentiality
LowIntegrity
LowAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Gallerycreator | SimpLy Gallery | affected 3.3.3.1 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| plugins.trac.wordpress.org/browser/simply-gallery-block/trunk/blocks/init.php | [email protected] | plugins.trac.wordpress.org | |
| www.wordfence.com/threat-intel/vulnerabilities/id/29b1984d-e6da-49d5-8b40-cdf2f... | [email protected] | www.wordfence.com | |
| plugins.trac.wordpress.org/browser/simply-gallery-block/trunk/blocks/init.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/simply-gallery-block/trunk/blocks/init.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/simply-gallery-block/tags/3.3.2.2/blocks/init.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/simply-gallery-block/trunk/blocks/init.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/changeset | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/simply-gallery-block/tags/3.3.2.2/blocks/init.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/simply-gallery-block/tags/3.3.2.2/blocks/init.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/simply-gallery-block/tags/3.3.2.2/blocks/init.php | [email protected] | plugins.trac.wordpress.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Muhammad Yudha - DJ (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-07-10T14:09:00.000Z | Disclosed |
There are currently no legacy QID mappings associated with this CVE.