Information disclosure in Post Grid Gutenberg Blocks

CVE-2026-86783

The Post Grid Gutenberg Blocks WordPress plugin before 5.0.41 does not perform an authorization or post-visibility check on a REST API route that returns the custom field keys of a given post, allowing unauthenticated users to disclose the custom field key names of arbitrary posts, including private, draft, pending, scheduled and password-protected posts.

Vulnerability class: Information Disclosure

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.002 (10.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 10th percentile — 10.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

  • Post Grid Gutenberg Blocks

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-86783?
CVE-2026-86783 is a medium-severity vulnerability in Post Grid Gutenberg Blocks, classified under Information Disclosure. CVSS score: 5.3/10. Published 2026-09-23.
How severe is CVE-2026-86783?
Medium severity. CVSS v3 base score is 5.3 out of 10.