dbcve.org
Missing AuthorizationWeakness · CWE-862

CVE-2026-12428

MEDIUM · 6.5 CVSS v3.1 Published 2026-07-09
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click 6 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
The Blocks for ACF Fields plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the get_all_values() function in the /wp-json/acf-field-blocks/v1/values REST endpoint in versions up to, and including, 1.6.2. The permission_callback only verifies the generic publish_posts capability and the handler passes a user-supplied id parameter directly to get_field_objects() without verifying that the requesting user is authorized to read the target object. This makes it possible for authenticated attackers, with Author-level access and above, to read ACF field values from arbitrary posts (including private posts, drafts, posts by other users, and other ACF-supported objects) that they should not have access to.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The Blocks for ACF Fields WordPress plugin has an Insecure Direct Object Reference (IDOR) vulnerability in its REST API endpoint /wp-json/acf-field-blocks/v1/values. The endpoint's permission_callback only checks the generic publish_posts capability and passes a user-supplied id parameter directly to get_field_objects() without verifying the requesting user has authorization to read the target post's ACF field values. This allows any authenticated user with Author-level access or higher to read ACF field data from arbitrary posts including private posts, drafts, and posts authored by other users.

MitigationUpdate to version 1.6.3 or later which should include proper capability checks. The fix requires implementing role-based access control that verifies the current user has appropriate read permissions for the specific post being requested.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm plugin installation and version
    Navigate to WordPress admin > Plugins and locate 'Blocks for ACF Fields' (or 'acf-field-blocks'), or inspect the plugin file header in wp-content/plugins/acf-field-blocks/readme.txt for the Version field
    Affected if The installed version is below 1.6.3 (e.g., 1.6.2, 1.6.1, 1.5.0, etc.)
  2. Verify the vulnerable REST endpoint exists
    Send a request to /wp-json/acf-field-blocks/v1/values or inspect the plugin's registration code for rest_route 'acf-field-blocks/v1/values'
    Affected if The endpoint is registered and responds to requests (even if returning error, the route exists)
  3. Test endpoint authorization behavior
    Using a low-privilege authenticated user (Author role), send a GET request to /wp-json/acf-field-blocks/v1/values?id={post_id} where {post_id} is a private post or a post authored by a different user
    Affected if The endpoint returns ACF field data for posts the user should not have permission to read (private posts, drafts, other users' posts)
  4. Inspect the permission_callback implementation
    Examine the plugin code where rest_api_register_hooks or register_rest_route is called for 'acf-field-blocks/v1/values' and check if permission_callback validates user can read the specific post by ID
    Affected if The permission_callback only checks a generic capability like 'publish_posts' without verifying post-specific read access

Your environment is affected if the Blocks for ACF Fields plugin is installed with a version below 1.6.3 AND the REST endpoint /wp-json/acf-field-blocks/v1/values is accessible to authenticated users who can read posts they do not own.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update to version 1.6.3 or later which should include proper capability checks. The fix requires implementing role-based access control that verifies the current user has appropriate read permissions for the specific post being requested.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,090
Get help mitigating

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-12428 in production — separate from our analysis above.

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What this is

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What belongs here
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