How severe is CVE-2017-6921?

CVE-2017-6921 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2017-6921 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-6921?

CVE-2017-6921 affects Drupal. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-6921?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2017-6921 published?

CVE-2017-6921 was published on 2019-01-15 and last updated on 2026-06-17.

CVE-2017-6921

CVE-2017-6921 is a medium-severity vulnerability in Drupal with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Drupal
Published: 2019-01-15
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2017-6921?: 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.
How severe is CVE-2017-6921?: CVE-2017-6921 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2017-6921 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-6921?: CVE-2017-6921 affects Drupal. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-6921?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-6921 published?: CVE-2017-6921 was published on 2019-01-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:drupal:drupal:*:*:*:*:*:*:*:*

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