What’s Vulnerable › Vulnerabilities

CVE-2020-13671: Drupal core Un-restricted Upload of File

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: yes — in CISA KEV since 2022-01-18
• EPSS: 36.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-11-20 · updated 2026-06-17
• Weakness: CWE-434

Description

Drupal core does not properly sanitize certain filenames on uploaded files, which can lead to files being interpreted as the incorrect extension and served as the wrong MIME type or executed as PHP for certain hosting configurations. This issue affects: Drupal Drupal Core 9.0 versions prior to 9.0.8, 8.9 versions prior to 8.9.9, 8.8 versions prior to 8.8.11, and 7 versions prior to 7.74.

Affected products

• Drupal: from 7.0 before 7.74; from 8.8.0 before 8.8.11; from 8.9.0 before 8.9.9; from 9.0.0 before 9.0.8 — fixed in 7.74, 8.8.11, 8.9.9, 9.0.8
• Fedoraproject Fedora: 32, 33

How to fix

Upgrade to a fixed version: Drupal 7.74, 8.8.11, 8.9.9, 9.0.8. Check the vendor advisory for mitigations.

References

• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5KSFM672XW3X6BR7TVKRD63SLZGKK437/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KWM4CTMEGAC4I2CHYNJVSROY4CVXVEUT/
• https://www.drupal.org/sa-core-2020-012
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5KSFM672XW3X6BR7TVKRD63SLZGKK437/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KWM4CTMEGAC4I2CHYNJVSROY4CVXVEUT/
• https://www.drupal.org/sa-core-2020-012
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-13671

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