How severe is CVE-2020-13671?

CVE-2020-13671 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-13671 being actively exploited?

Yes. CVE-2020-13671 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-01-18, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2020-13671?

CVE-2020-13671 primarily affects Drupal. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-13671?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2020-13671 have an EU (EUVD) identifier?

Yes. CVE-2020-13671 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-2168. It is also flagged as exploited in the EUVD (since 2022-01-18).

When was CVE-2020-13671 published?

CVE-2020-13671 was published on 2020-11-20 and last updated on 2026-06-17.

CVE-2020-13671

CVE-2020-13671 is a high-severity vulnerability in Drupal with a CVSS 3.x base score of 8.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-01-18). The underlying weakness is classified as CWE-434.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-01-18)
EU (EUVD) id: EUVD-2021-2168
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-01-18)
Weakness: CWE-434
Affected product: Drupal
Published: 2020-11-20
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2020-13671?: 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.
How severe is CVE-2020-13671?: CVE-2020-13671 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-13671 being actively exploited?: Yes. CVE-2020-13671 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-01-18, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2020-13671?: CVE-2020-13671 primarily affects Drupal. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-13671?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2020-13671 have an EU (EUVD) identifier?: Yes. CVE-2020-13671 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-2168. It is also flagged as exploited in the EUVD (since 2022-01-18).
When was CVE-2020-13671 published?: CVE-2020-13671 was published on 2020-11-20 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:drupal:drupal:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*

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