# CVE-2020-13671: Drupal core Unrestricted Upload of File with Dangerous Type

Source: https://junglewise.ai/threats/cve-2020-13671-drupal-core-un-restricted-upload-of-file  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-10-12. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2020-13671 · Severity: critical · CVSS 3.1 · Exploited in the wild · Published 2021-10-12

Drupal core fails to properly sanitize filenames on uploaded files, allowing files with multiple extensions to bypass security filters. This can lead to files being executed as PHP or served with incorrect MIME types, potentially resulting in remote code execution depending on the hosting configuration.

Technologies: [Drupal Core](https://junglewise.ai/threats/technologies/drupal-core), [drupal/core (Packagist)](https://junglewise.ai/threats/technologies/packagist-drupal-core), [drupal/drupal (Packagist)](https://junglewise.ai/threats/technologies/drupal-drupal). Vendors: [Drupal](https://junglewise.ai/threats/vendors/drupal), [Packagist](https://junglewise.ai/threats/vendors/packagist).

## Quick answers

**Is CVE-2020-13671 exploited in the wild?** Yes. CVE-2020-13671 is known to be exploited in the wild, first recorded on 18 January 2022. Treat it as urgent.

**How severe is CVE-2020-13671?** Critical severity, with a CVSS score of 3.1, published 12 October 2021.

**Which products and versions are affected?** drupal/core (Packagist) ECOSYSTEM:introduced=8.0.0,fixed=8.8.11|ECOSYSTEM:introduced=8.9.0,fixed=8.9.9|ECOSYSTEM:introduced=9.0.0,fixed=9.0.8, ECOSYSTEM:introduced=9.0.0,fixed=9.0.8; drupal/drupal (Packagist) ECOSYSTEM:introduced=7.0.0,fixed=7.74.

**Is there a fix for CVE-2020-13671?** Yes. drupal/core (Packagist): upgrade to 8.8.11, 9.0.8 or later; drupal/drupal (Packagist): upgrade to 7.74 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2020-13671 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2020-13671?** Check whether you run Drupal Core, drupal/core (Packagist) or drupal/drupal (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

- drupal/core (Packagist): upgrade to 8.8.11, 9.0.8 or later

  ```sh
  composer require drupal/core:^9.0.8
  ```

- drupal/drupal (Packagist): upgrade to 7.74 or later

  ```sh
  composer require drupal/drupal:^7.74
  ```


## Affected products

- Drupal Drupal Core 7 versions prior to 7.74, 8.8 versions prior to 8.8.11, 8.9 versions prior to 8.9.9, 9.0 versions prior to 9.0.8

## Identifiers

- CVE-2020-13671
- DRUPAL-CORE-2020-012
- GHSA-68jc-v27h-vhmw

## Timeline

- 2020-11-18: advisory: Original vendor advisory SA-CORE-2020-012 published
- 2022-01-18: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2022-01-18: disclosed: NVD publication date

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