CVE-2026-86783 PostX < 5.0.41 - Unauthenticated Custom Field Key Disclosure via REST API
Unauthenticated attackers can disclose custom field keys of private or protected posts via an unprotected REST API route in the Post Grid Gutenberg Blocks plugin.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-86783?
CVE-2026-86783 is a medium-severity vulnerability in Unknown Post Grid Gutenberg Blocks, published on 23 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-200
Which versions are affected by CVE-2026-86783?
How do I fix CVE-2026-86783?
No fix has been published for CVE-2026-86783 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-86783 being exploited?
There is no known exploitation of CVE-2026-86783 in the wild and no public exploit code.
Sources
Also known as GHSA-f7w9-vf85-gjj5.