Instant Popup Builder <= 1.1.7 — Unauthenticated Arbitrary Shortcode Execution via 'token' Parameter

Am I affected?

• Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under Instant Popup Builder – Popup Maker for Videos, Forms, Offers, Announcements, Galleries & Exit Intent.
• No admin access? Run a passive check of your site. It reads public files only.
• No account is needed to exploit this. Treat any exposed site on an affected version as at risk.

What to do

1. Update to version 1.1.8, or a newer patched version
2. Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
3. Watch Instant Popup Builder – Popup Maker for Videos, Forms, Offers, Announcements, Galleries & Exit Intent to get an email when the next vulnerability is published.

Advisory

Source description from Wordfence Intelligence, credited to theviper17y.

The Instant Popup Builder plugin for WordPress is vulnerable to Unauthenticated Arbitrary Shortcode Execution in all versions up to and including 1.1.7. This is due to the handle_email_verification_page() function constructing a shortcode string from user-supplied GET parameters (token, email) and passing it to do_shortcode() without properly sanitizing square bracket characters, combined with missing authorization checks on the init hook. While sanitize_text_field() and esc_attr() are applied, neither function strips or escapes square bracket characters ([ and ]). WordPress's shortcode regex uses [^\]\/]* to match content inside shortcode tags, meaning a ] character in the token value prematurely closes the shortcode tag. This makes it possible for unauthenticated attackers to inject and execute arbitrary registered shortcodes by crafting a malicious token parameter containing ] followed by arbitrary shortcode syntax.

Exploits & references

Proof-of-concept & detection

No public proof-of-concept or detection template is known for this vulnerability.

Advisories & patches

• Advisorywordfence.com

Related CVEs

Timeline

1. Mar 18, 2026

   CVE published

   Severity medium, CVSS 5.3

2. Nov 13, 2026

   Record last updated