CVE-2021-24826: Custom Content Shortcode < 4.0.2 - Authenticated Stored Cross-Site Scripting

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2022-03-07 · updated 2026-06-17
Weakness: CWE-79

Description

The Custom Content Shortcode WordPress plugin before 4.0.2 does not escape custom fields before outputting them, which could allow Contributor+ (v < 4.0.1) or Admin+ (v < 4.0.2) users to perform Cross-Site Scripting attacks even when the unfiltered_html is disallowed. Please note that such attack is still possible by admin+ in single site blogs by default (but won't be when the unfiltered_html is disallowed)

Affected products

Custom Content Shortcode: before 4.0.2 — fixed in 4.0.2

How to fix

Upgrade to a fixed version: Custom Content Shortcode 4.0.2. Check the vendor advisory for mitigations.

References

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