# CVE-2026-40731: Mikado-Themes ChapterOne Local File Inclusion

Source: https://junglewise.ai/threats/cve-2026-40731-mikado-themes-chapterone-local-file-inclusion  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-17. Updated: 2026-06-17  
License: CC BY 4.0 with a link back

CVE-2026-40731 · Severity: high · CVSS 8.1 · Published 2026-06-17

The ChapterOne theme for WordPress is vulnerable to a security flaw that allows unauthorized individuals to access sensitive files on the web server. By exploiting this vulnerability, an attacker could view internal configuration files, potentially exposing database credentials and leading to a full site takeover. This issue affects all versions of the theme up to and including 1.7.

Vendors: [Mikado-Themes](https://junglewise.ai/threats/vendors/mikado-themes).

## Quick answers

**Is CVE-2026-40731 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-40731 being exploited in the wild.

**How severe is CVE-2026-40731?** High severity, with a CVSS score of 8.1, published 17 June 2026.

**Which products and versions are affected?** Mikado-Themes ChapterOne <= 1.7.

**Is there a fix for CVE-2026-40731?** 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-2026-40731 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-40731?** Check whether you run Mikado-Themes ChapterOne at an affected version. 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

A Local File Inclusion (LFI) vulnerability exists in the ChapterOne WordPress theme due to improper control of filenames in PHP include/require statements (CWE-98). The flaw allows an unauthenticated remote attacker to manipulate input to include local files from the server's filesystem. While the attack complexity is rated as high, a successful exploit can lead to the disclosure of sensitive information such as wp-config.php, which contains database credentials. The vulnerability is addressed in version 1.8 of the theme.

## Affected products

- Mikado-Themes ChapterOne <= 1.7

## Timeline

- 2026-02-10: other: Vulnerability reported by researcher
- 2026-04-16: advisory: Initial disclosure by Patchstack
- 2026-06-17: disclosed: CVE published to NVD

## References

- [https://wordpress.org/themes](https://wordpress.org/themes)
- [https://patchstack.com/database/wordpress/theme/chapterone/vulnerability/wordpress-chapterone-theme-1-7-local-file-inclusion-vulnerability?_s_id=cve](https://patchstack.com/database/wordpress/theme/chapterone/vulnerability/wordpress-chapterone-theme-1-7-local-file-inclusion-vulnerability?_s_id=cve)