Auth bypass in Drupal Webform Rest

CVE-2026-16644

Incorrect Authorization vulnerability in Drupal Webform REST allows Forceful Browsing. This issue affects Webform REST versions: from 0.0.0 to 4.1.0.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.003 (22.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 22.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-16644: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-16644?
CVE-2026-16644 is a critical-severity vulnerability in Drupal Webform Rest, classified under Incorrect Authorization. CVSS score: 9.1/10. Published 2026-08-25.
How severe is CVE-2026-16644?
Critical severity. CVSS v3 base score is 9.1 out of 10.