CVE-2023-5161: Modal Window <= 5.3.5 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-09-27 · updated 2026-06-17
Weakness: CWE-79

Description

The Modal Window plugin for WordPress is vulnerable to Stored Cross-Site Scripting via shortcodes in versions up to, and including, 5.3.5 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers with contributor-level and above permissions to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Affected products

wpcalc Modal Window – create popup modal window: through 5.3.5

References

https://plugins.trac.wordpress.org/browser/modal-window/tags/5.3.5/public/class-public.php#L73
https://plugins.trac.wordpress.org/browser/modal-window/tags/5.3.5/public/shortcode.php#L53
https://plugins.trac.wordpress.org/changeset/2971132/modal-window#file195
https://plugins.trac.wordpress.org/changeset/2971132/modal-window#file196
https://www.wordfence.com/threat-intel/vulnerabilities/id/48e2129f-6a2c-45e4-a0cf-7d8d5f563a7f?source=cve
https://plugins.trac.wordpress.org/browser/modal-window/tags/5.3.5/public/class-public.php#L73
https://plugins.trac.wordpress.org/browser/modal-window/tags/5.3.5/public/shortcode.php#L53
https://plugins.trac.wordpress.org/changeset/2971132/modal-window#file195
https://plugins.trac.wordpress.org/changeset/2971132/modal-window#file196
https://www.wordfence.com/threat-intel/vulnerabilities/id/48e2129f-6a2c-45e4-a0cf-7d8d5f563a7f?source=cve

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