Is CVE-2026-84021 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-84021 being exploited in the wild.

How severe is CVE-2026-84021?

Medium severity, with a CVSS score of 6.8, published 5 September 2026.

Which products and versions are affected?

Bold Page Builder before 5.9.8.

Is there a fix for CVE-2026-84021?

A patch was published on 2026-09-05: Fixed in version 5.9.8 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-84021 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-84021?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-84021: Bold Page Builder stored XSS via link URL validation bypass

CVE-2026-84021 · Severity: medium · CVSS 6.8 · Published 2026-09-05

The Bold Page Builder WordPress plugin used to create custom page layouts does not properly validate URLs in shortcodes, allowing contributors and above to inject malicious scripts. When a user clicks a crafted link in a published page, the malicious script executes in their browser, enabling attackers to steal session data, modify page content, or perform actions on behalf of the victim.

Quick answers

Is CVE-2026-84021 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-84021 being exploited in the wild.
How severe is CVE-2026-84021?: Medium severity, with a CVSS score of 6.8, published 5 September 2026.
Which products and versions are affected?: Bold Page Builder before 5.9.8.
Is there a fix for CVE-2026-84021?: A patch was published on 2026-09-05: Fixed in version 5.9.8 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-84021 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-84021?: Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability is a stored cross-site scripting (XSS) flaw in the bt_bb_button, bt_bb_headline, and bt_bb_icon shortcode handlers. The plugin relies on a filter to validate link URLs before output in HTML attributes, but the filter can be evaded by embedding a literal tab character (0x09) between the JavaScript protocol scheme and the script keyword (e.g., java[TAB]script:). The browser's URL parser strips the tab during parsing, reassembling the javascript: scheme and executing the injected code. Attack requires Contributor role or above; no special configuration is needed. The vulnerability is fixed in version 5.9.8.

Affected products

Bold Page Builder before 5.9.8

Timeline

2026-09-03: disclosed
2026-09-05: patched: Fixed in version 5.9.8

References

https://wpscan.com/vulnerability/ca226eab-59a2-42d5-96f6-84dacf7c6c5a/

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