CVE-2020-13671: Drupal core Un-restricted Upload of File
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 18 Jan 2022, 424 days after the CVE record was published.
- How likely is exploitation in the next 30 days?
- 36.2%
EPSS score, percentile 98.5 of all scored records
- How severe?
- 8.8 High
CVSS v3.1 base score, from CISA's enrichment of the record
- What should I do?
Required action (CISA), due 18 Jul 2022: Apply updates per vendor instructions.
- Which versions are affected?
Affected: 9.0 versions prior to 9.0.8; 8.9 versions prior to 8.9.9; 8.8 versions prior to 8.8.11; 7 versions prior to 7.74
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
What to do
Required action, set by CISA
Apply updates per vendor instructions.
CISA due date for this action: 18 July 2022.
Advisories and patches
Linked from CISA's catalog entry
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | 9.0 versions prior to 9.0.8 |
| Affected | 8.9 versions prior to 8.9.9 |
| Affected | 8.8 versions prior to 8.8.11 |
| Affected | 7 versions prior to 7.74 |
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
About this vulnerability
Improper sanitization in the extension file names is present in Drupal core.
Summary: CISA's KEV catalog, as of 28 Oct 2026.
- CISA added CVE-2020-13671 to its Known Exploited Vulnerabilities (KEV) catalog on 18 Jan 2022.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 18 Jul 2022.
- The CVE record was published on 20 Nov 2020, 424 days before it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 8.8 (High), taken from CISA's enrichment of the record.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 36.2% (percentile 98.5), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.
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.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
Weakness
- CWE-434: Unrestricted Upload of File with Dangerous Type
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| 20 Nov 2020 | CVE record published |
| 18 Jan 2022 | Added to CISA KEV |
| 18 Jul 2022 | CISA due date for the required action |
| 21 Oct 2025 | CVE record last updated |
References
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