CVE-2026-1242: BlockSpare - Gutenberg Site Builder Blocks & Starter Sites <= 4.2.6 - Incorrect Authorization to Authenticated (Subscriber+) Arbitrary Post Creation

Published Sep 19, 2026
·
Updated

The BlockSpare plugin for WordPress is vulnerable to authorization bypass due to incorrect logic in the permission callback in all versions up to, and including, 4.2.6 due to the use of an AND (&&) operator instead of an OR (||) operator. This makes it possible for authenticated attackers, with Subscriber-level access and above, to bypass authorization checks and create arbitrary posts.

Affected Software

2 affected components
WordPress
WordPress plugin/BlockSpare - Gutenberg Site Builder Blocks & Starter Sites<=4.2.6

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade wordpress/blockspare to a version that resolves this vulnerability.

    Fixed in 4.2.6

Event History

Sep 19, 2026
CVE Published
via MITRE·07:43 AM
Data Sourced
via MITRE·07:43 AM
DescriptionSeverityWeakness

Frequently Asked Questions

1

Who can exploit this issue?

An attacker needs an authenticated WordPress account with at least Subscriber-level access. No user interaction is required.

2

What can a successful attacker do?

They can bypass the affected authorization check and create arbitrary posts.

3

How can I determine whether my site is affected?

Sites using the BlockSpare - Gutenberg Site Builder Blocks & Starter Sites plugin at version 4.2.6 or earlier are affected.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
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