# CVE-2026-24907: October CMS has Stored XSS in Event Log Mail Preview

Source: https://junglewise.ai/threats/cve-2026-24907-october-cms-has-stored-xss-in-event-log-mail-preview  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-14. Updated: 2026-05-11  
License: CC BY 4.0 with a link back

CVE-2026-24907 · Severity: medium · CVSS 5.4 · Published 2026-04-14

October is a Content Management System (CMS) and web platform. Versions prior to 3.7.14 and 4.1.10 contain a stored cross-site scripting (XSS) vulnerability in the Event Log mail preview feature. When viewing logged mail messages, HTML content was rendered in an iframe without proper sandboxing, allowing JavaScript execution in the viewer's browser context. This issue has been fixed in versions 3.7.14 and 4.1.10. If users are unable to update immediately, workarounds include restricting mail template editing permissions to fully trusted administrators only and restricting Event Log viewing permissions to minimize exposure.

Technologies: [Octobercms October](https://junglewise.ai/threats/technologies/october), [october/system (Packagist)](https://junglewise.ai/threats/technologies/october-system). Vendors: [Octobercms](https://junglewise.ai/threats/vendors/octobercms), [Packagist](https://junglewise.ai/threats/vendors/packagist).

## Quick answers

**Is CVE-2026-24907 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-24907 being exploited in the wild.

**How severe is CVE-2026-24907?** Medium severity, with a CVSS score of 5.4, published 14 April 2026.

**Which products and versions are affected?** october/system (Packagist) ECOSYSTEM:introduced=4.0.0,fixed=4.1.10.

**Is there a fix for CVE-2026-24907?** Yes. october/system (Packagist): upgrade to 4.1.10 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2026-24907?** Check whether you run Octobercms October or october/system (Packagist) 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.

## How to fix

- october/system (Packagist): upgrade to 4.1.10 or later

  ```sh
  composer require october/system:^4.1.10
  ```


## Affected products

- Octobercms October
- october/system (Packagist) ECOSYSTEM:introduced=4.0.0,fixed=4.1.10

## Identifiers

- CVE-2026-24907
- GHSA-j4j5-9x6g-rgxc

## References

- [https://api.github.com/users/Neosprings](https://api.github.com/users/Neosprings)
- [https://github.com/Neosprings](https://github.com/Neosprings)
- [https://api.github.com/users/Neosprings/gists%7B/gist_id%7D](https://api.github.com/users/Neosprings/gists%7B/gist_id%7D)
- [https://api.github.com/users/Neosprings/repos](https://api.github.com/users/Neosprings/repos)
- [https://avatars.githubusercontent.com/u/149110916?v=4](https://avatars.githubusercontent.com/u/149110916?v=4)
- [https://api.github.com/users/Neosprings/events%7B/privacy%7D](https://api.github.com/users/Neosprings/events%7B/privacy%7D)

## Related threats

- [October CMS PHP object injection in widget session storage](https://junglewise.ai/threats/cve-2026-49400-october-cms-php-object-injection-in-widget-session-storage)
- [October CMS Twig sandbox bypass in Safe Mode](https://junglewise.ai/threats/cve-2026-46696-october-cms-twig-sandbox-bypass-in-safe-mode)
- [October CMS: Editor Sub-Permission Bypass for Asset and Blueprint File Operations](https://junglewise.ai/threats/cve-2026-29179-october-cms-editor-sub-permission-bypass-for-asset-and-blueprint)
- [October CMS: Reflected XSS via DataTable Form Widget](https://junglewise.ai/threats/cve-2026-27937-october-cms-reflected-xss-via-datatable-form-widget)
- [October CMS has Safe Mode Bypass via CSS Preprocessor Compilers](https://junglewise.ai/threats/cve-2026-26067-october-cms-has-safe-mode-bypass-via-css-preprocessor-compilers)