# CVE-2026-107848: Contao: Cross-site request forgery in custom backend actions

Source: https://junglewise.ai/threats/cve-2026-107848-contao-cross-site-request-forgery-in-custom-backend-actions  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-09  
License: CC BY 4.0 with a link back

CVE-2026-107848 · Severity: low · CVSS 3.5 · Published 2026-10-09

Contao is an Open Source CMS. From version 4.0.0 until 5.3.50 and 5.7.12, RequestTokenListener validates REQUEST_TOKEN only for POST requests, while the declarative GET guard runs only when an act parameter is present. Backend actions dispatched through the key parameter can therefore execute without a CSRF token when an authenticated backend user loads an attacker-controlled URL. Reachable actions remain limited to modules available to that user, and the advisory demonstrates destructive or state-changing actions rather than privilege escalation. This issue is fixed in versions 5.3.50 and 5.7.12.

Technologies: [contao/core-bundle (Packagist)](https://junglewise.ai/threats/technologies/contao-core-bundle). Vendors: [Packagist](https://junglewise.ai/threats/vendors/packagist).

## Quick answers

**Is CVE-2026-107848 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-107848 being exploited in the wild.

**How severe is CVE-2026-107848?** Low severity, with a CVSS score of 3.5, published 9 October 2026.

**Which products and versions are affected?** contao/core-bundle (Packagist) ECOSYSTEM:introduced=4.0.0,fixed=5.3.50.

**Is there a fix for CVE-2026-107848?** Yes. contao/core-bundle (Packagist): upgrade to 5.3.50 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2026-107848?** Check whether you run contao/core-bundle (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

- contao/core-bundle (Packagist): upgrade to 5.3.50 or later

  ```sh
  composer require contao/core-bundle:^5.3.50
  ```


## Affected products

- contao/core-bundle (Packagist) ECOSYSTEM:introduced=4.0.0,fixed=5.3.50

## Identifiers

- CVE-2026-107848
- GHSA-9ff2-p842-45wq

## Related threats

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- [Contao improper access control in preview links module](https://junglewise.ai/threats/cve-2026-107850-contao-improper-access-control-in-the-preview-links-module)
- [Contao path traversal in images controller](https://junglewise.ai/threats/cve-2026-107844-contao-path-traversal-in-the-images-controller)
- [Contao registration module unvalidated mail resend](https://junglewise.ai/threats/cve-2026-107843-contao-the-registration-module-re-sends-activation-mails)
- [Contao protected page content disclosure via search index](https://junglewise.ai/threats/cve-2026-107842-contao-protected-page-content-is-disclosed-to-anonymous-visitors)