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.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Base score: 8.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 35%
- Percentile among all scored CVEs: 98
- Score date: 10/8/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
CISA KEV — actively exploited
- Added to catalog: 1/18/2022
- Remediation due date: 7/18/2022
- Known ransomware use: Unknown
💥 Public exploits
Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.
- Proof of concept on GitHub (unverified) · List of proofs of concept on GitHub
⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.
🎯 ATT&CK techniques
How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.
- Exploitation
T1210Exploitation of Remote Serviceslateral movement75 % - Primary impact
T1505.003Web Shellpersistence85 % - Secondary impact
T1565.001Stored Data Manipulationimpact65 %
Explotación corregida por reglas (vector CVSS): era T1190
Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.
🛡️ ATT&CK mitigations that cover these techniques
Affected technologies (2)
CWEs
- CWE-434
- CWE-434
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
Raw JSON (NVD)
Show
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