CVE-2026-5743: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in gallerycreator SimpLy Gallery
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.
CVE-2026-5743: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in gallerycreator SimpLy Gallery
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.
CVSS v3.1
Score 6.4medium
Weaknesses
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Wordfence
- Date Reserved
- 2026-04-07T13:48:55.983Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a51b98168715ace430ae4e6
Added to database: 07/11/2026, 03:33:21 UTC
Last updated: 07/11/2026, 03:33:21 UTC
Views: 1
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