CVE-2026-16644Network attack vector

Authenticated submission access via missing parent permission checks

Published Aug 25, 2026 · Updated Aug 25, 2026

Incorrect authorization in Drupal Webform REST 4.0.3 and earlier allows remote authenticated users to view or alter submissions via REST endpoints. Its REST submission resources execute create, retrieve, and update operations without checking the parent webform's corresponding access settings. Access to the configured REST resource is required, bounding exposure to users who already hold that resource permission while bypassing form-level restrictions.

CVSS severity9.1
Critical
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect authorization in Drupal Webform REST 4.0.3 and earlier allows remote authenticated users to view or alter submissions via REST endpoints. Its REST submission resources execute create, retrieve, and update operations without checking the parent webform's corresponding access settings. Access to the configured REST resource is required, bounding exposure to users who already hold that resource permission while bypassing form-level restrictions.

The record

CVE
CVE-2026-16644
Published
Aug 25, 2026
Updated
Aug 25, 2026
Vendor
OAuth.js
Product
Webform REST
Classifications
CWE-863, CAPEC-87, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.0.0 <4.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

OAuth.js · Webform RESTversion=0.0.0 <4.1.0

Published CVSS scores

9.1CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization
CAPEC-87Forceful Browsing
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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