# CVE-2026-8891: Bit Apps BitForm Stored XSS in bitform shortcode

Source: https://junglewise.ai/threats/cve-2026-8891-bit-apps-bitform-stored-xss-in-bitform-shortcode  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-27. Updated: 2026-05-27  
License: CC BY 4.0 with a link back

CVE-2026-8891 · Severity: medium · CVSS 6.4 · Published 2026-05-27

BitForm is a WordPress plugin used to create and manage forms on websites. A security flaw allows users with contributor-level access or higher to inject malicious scripts into pages via form shortcodes. When other users or administrators visit these pages, the scripts execute automatically, which could lead to unauthorized actions or data theft.

Technologies: [Bit Apps Bit Form](https://junglewise.ai/threats/technologies/bit-form). Vendors: [Bit Apps](https://junglewise.ai/threats/vendors/bit-apps).

## Quick answers

**Is CVE-2026-8891 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-8891 being exploited in the wild.

**How severe is CVE-2026-8891?** Medium severity, with a CVSS score of 6.4, published 27 May 2026.

**Which products and versions are affected?** Bit Apps BitForm Up to, and including, 1.1.0.

**Is there a fix for CVE-2026-8891?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-8891 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-8891?** Check whether you run Bit Apps Bit Form. 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 BitForm plugin for WordPress is vulnerable to Stored Cross-Site Scripting (XSS) due to insufficient input sanitization and output escaping in the Shortcode::shortcode() function. Specifically, user-supplied attributes such as 'width' and 'height' within the 'bitform' shortcode are interpolated directly into the 'style' attribute of an <iframe> element. An authenticated attacker with contributor-level permissions or higher can exploit this to inject arbitrary web scripts. These scripts are stored on the server and execute in the context of any user's browser who views the affected page. The vulnerability exists in all versions up to and including 1.1.0.

## Affected products

- Bit Apps BitForm Up to, and including, 1.1.0

## Timeline

- 2026-05-27: disclosed: Initial publication of the CVE record.
- 2026-05-27: advisory: Wordfence published the vulnerability details.

## References

- [https://plugins.trac.wordpress.org/browser/bitform/tags/1.1.0/Common/Shortcode.php](https://plugins.trac.wordpress.org/browser/bitform/tags/1.1.0/Common/Shortcode.php)
- [https://plugins.trac.wordpress.org/browser/bitform/tags/1.1.0/Common/Shortcode.php](https://plugins.trac.wordpress.org/browser/bitform/tags/1.1.0/Common/Shortcode.php)
- [https://plugins.trac.wordpress.org/browser/bitform/tags/1.1.0/index.php](https://plugins.trac.wordpress.org/browser/bitform/tags/1.1.0/index.php)
- [https://www.wordfence.com/threat-intel/vulnerabilities/id/71167dec-38ec-4eb3-8fab-25eca0f8b071?source=cve](https://www.wordfence.com/threat-intel/vulnerabilities/id/71167dec-38ec-4eb3-8fab-25eca0f8b071?source=cve)

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- [Bit Apps Bit Form stored XSS in Conversational Form Progress Label](https://junglewise.ai/threats/cve-2025-15669-bit-apps-bit-form-stored-xss-in-conversational-form-progress)
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- [Bit Form WordPress Plugin arbitrary file deletion in deleteFiles](https://junglewise.ai/threats/cve-2026-14372-bit-form-wordpress-plugin-arbitrary-file-deletion-in-deletefiles)