CVE-2017-6921
File REST resource does not properly validate
In Drupal 8 prior to 8.3.4; The file REST resource does not properly validate some fields when manipulating files. A site is only affected by this if the site has the RESTful Web Services (rest) module enabled, the file REST resource is enabled and allows PATCH requests, and an attacker can get or register a user account on the site with permissions to upload files and to modify the file resource.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
In Drupal 8 prior to 8.3.4; The file REST resource does not properly validate some fields when manipulating files. A site is only affected by this if the site has the RESTful Web Services (rest) module enabled, the file REST resource is enabled and allows PATCH requests, and an attacker can get or register a user account on the site with permissions to upload files and to modify the file resource.
- Record
CVE-2017-6921- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:P/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
CVE List No score
File REST resource does not properly validate
In Drupal 8 prior to 8.3.4; The file REST resource does not properly validate some fields when manipulating files. A site is only affected by this if the site has the RESTful Web Services (rest) module enabled, the file REST resource is enabled and allows PATCH requests, and an attacker can get or register a user account on the site with permissions to upload files and to modify the file resource.
- Record
CVE-2017-6921- Updated
- 2026-11-02
EUVDEUVD-2022-4050 No score
In Drupal 8 prior to 8.3.4; The file REST resource does not properly validate some fields when manipulating files. A site is only affected by this if the site has the RESTful Web Services (rest) module enabled, the file REST resource is enabled and allows PATCH requests, and an attacker can get or register a user account on the site with permissions to upload files and to modify the file resource.
- Record
EUVD-2022-4050- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-h377-287m-w2r9
Drupal file REST resource does not properly validate
In Drupal 8 prior to 8.3.4; The file REST resource does not properly validate some fields when manipulating files. A site is only affected by this if the site has the RESTful Web Services (rest) module enabled, the file REST resource is enabled and allows PATCH requests, and an attacker can get or register a user account on the site with permissions to upload files and to modify the file resource.
- Record
GHSA-h377-287m-w2r9- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
OSV
In Drupal 8 prior to 8.3.4; The file REST resource does not properly validate some fields when manipulating files. A site is only affected by this if the site has the RESTful Web Services (rest) module enabled, the file REST resource is enabled and allows PATCH requests, and an attacker can get or register a user account on the site with permissions to upload files and to modify the file resource.
- Record
CVE-2017-6921- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVGHSA-h377-287m-w2r9
Drupal file REST resource does not properly validate
In Drupal 8 prior to 8.3.4; The file REST resource does not properly validate some fields when manipulating files. A site is only affected by this if the site has the RESTful Web Services (rest) module enabled, the file REST resource is enabled and allows PATCH requests, and an attacker can get or register a user account on the site with permissions to upload files and to modify the file resource.
- Record
GHSA-h377-287m-w2r9- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
drupal/corePackagist |
8.0 up to 8.3.4 | 8.3.4 |
drupal/drupalPackagist |
8.0 up to 8.3.4 | 8.3.4 |
drupal/corePackagist |
8.0 up to 8.3.4, plus listed versions 8.0.08.0.0-beta108.0.0-beta118.0.0-beta128.0.0-beta13 Show 45 moreShow less8.0.0-beta148.0.0-beta158.0.0-beta168.0.0-beta68.0.0-beta78.0.0-beta88.0.0-beta98.0.0-rc18.0.0-rc28.0.0-rc38.0.0-rc48.0.18.0.28.0.38.0.48.0.58.0.68.1.08.1.0-beta18.1.0-beta28.1.0-rc18.1.18.1.108.1.28.1.38.1.48.1.58.1.68.1.78.1.88.1.98.2.08.2.0-beta18.2.0-beta28.2.0-beta38.2.0-rc18.2.0-rc28.2.18.2.28.2.38.2.48.2.58.2.68.2.78.2.8 |
8.3.4 |
drupal/drupalPackagist |
8.0 up to 8.3.4, plus listed versions 8.0.08.0.0-alpha148.0.0-alpha158.0.0-beta18.0.0-beta10 Show 45 moreShow less8.0.0-beta118.0.0-beta128.0.0-beta138.0.0-beta148.0.0-beta158.0.0-beta168.0.0-beta28.0.0-beta38.0.0-beta48.0.0-beta58.0.0-beta68.0.0-beta78.0.0-beta98.0.0-rc18.0.0-rc28.0.0-rc38.0.0-rc48.0.18.0.28.0.38.0.48.0.58.0.68.1.08.1.0-beta18.1.0-beta28.1.0-rc18.1.18.1.108.1.28.1.38.1.48.1.58.1.68.1.78.1.88.1.98.2.08.2.0-beta18.2.0-beta28.2.0-beta38.2.0-rc18.2.0-rc28.2.18.2.2 |
8.3.4 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2017-6921 is a medium vulnerability (CVSS 5.9) in Drupal, published January 15, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.83%, the 79th percentile. Fixed in drupal/core 8.3.4.
References
securityfocus.com/bid/99222
drupal.org/forum/newsletters/security-advisories-for-drupal-core/2017-06-21/drupal-core-multiple
securitytracker.com/id/1038781
nvd.nist.gov/vuln/detail/CVE-2017-6921
github.com/FriendsOfPHP/security-advisories/blob/master/drupal/core/CVE-2017-6921.yaml
Left out here: 22 versions. The JSON record has them.