CVE-2026-3600: The Investi plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'investi-announcements-accordion' shortcode's 'maximum-num-years...

Description

The Investi plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'investi-announcements-accordion' shortcode's 'maximum-num-years' attribute in all versions up to, and including, 1.0.26. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes. Specifically, the 'maximum-num-years' attribute value is read directly from shortcode attributes and interpolated into a double-quoted HTML attribute without any escaping (no esc_attr(), htmlspecialchars(), or similar). 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.

Metrics

CVSS 3.1

6.4/10

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

EPSS Probability

0.26%

17.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

References

Timeline

Published: Apr 8, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-3600?

The Investi plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'investi-announcements-accordion' shortcode's 'maximum-num-years' attribute in all versions up to, and including, 1.0.26. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes. Specifically, the 'maximum-num-years' attribute value is read directly from shortcode attributes and interpolated into a double-quoted HTML attribute without any escaping (no esc_attr(), htmlspecialchars(), or similar). 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.

How severe is CVE-2026-3600?

CVE-2026-3600 has a CVSS score of 6.4/10 (MEDIUM severity). The EPSS model estimates a 0.26% probability of exploitation in the next 30 days.

How do I fix CVE-2026-3600?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.