CVE-2026-12428 json
Blocks for ACF Fields <= 1.6.2 - Missing Authorization to Authenticated (Author+) Arbitrary ACF Field Value Disclosure via 'id' Parameter
published 4mo ago modified 4mo ago also EUVD-2026-42568
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 41%
- public exploits
- 0
- none known
Summary
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.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4mo ago
Exploit prediction
0.48% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
Affected products
- gamaup Blocks for ACF Fields — Display Custom Fields in the Block Editor
Classification
- Weakness
-
- CWE-862 Missing Authorization
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/fc48f75d-a2e8-49ea-9bfa-a27a61ff8a84?source=cve
- plugins.trac.wordpress.org /browser/acf-field-blocks/tags/1.6.0/inc/class-rest.php#L302
- plugins.trac.wordpress.org /browser/acf-field-blocks/tags/1.6.0/inc/class-rest.php#L100
- plugins.trac.wordpress.org /browser/acf-field-blocks/tags/1.6.0/inc/class-rest.php#L296
- plugins.trac.wordpress.org /browser/acf-field-blocks/tags/1.5.0/inc/class-rest.php#L302
- plugins.trac.wordpress.org /browser/acf-field-blocks/tags/1.5.0/inc/class-rest.php#L100
- plugins.trac.wordpress.org /browser/acf-field-blocks/tags/1.5.0/inc/class-rest.php#L296
- plugins.trac.wordpress.org /changeset?reponame=&old=3587876%40acf-field-blocks&new=3587876%40acf-field-blocks
Sources
- CVE List CVE-2026-12428
- NVD CVE-2026-12428
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