CVE-2026-1242

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

2026-09-18 19:07
Osvaldo Noe Gonzalez Del Rio (Os)

Strategic Overview

Status
Patched in 5.0.0
Affected Plugin
BlockSpare – Gutenberg Blocks, AI Content Generator & Site Builder for news, magazine, blog and business sites
Affected Version
<= 4.2.6
CVSS
4.3Medium
Weakness type
CWE-863 · Incorrect Authorization
CVE
CVE-2026-1242
View all BlockSpare – Gutenberg Blocks, AI Content Generator & Site Builder for news, magazine, blog and business sites vulnerabilities

At a glance

CVE-2026-1242 is a medium-severity Incorrect Authorization vulnerability in the BlockSpare WordPress plugin, affecting versions <= 4.2.6. It carries a CVSS score of 4.3 (reachable over the network; low attack complexity). Exploitation requires an authenticated account at Subscriber level or above. The issue is fixed in version 5.0.0; sites on affected versions should update now. Disclosed September 2026, reported by Osvaldo Noe Gonzalez Del Rio (Os).

Vulnerability Overview

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.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user.

CWE-863: Incorrect Authorization

Reaching this weakness in BlockSpare <= 4.2.6 takes an account at Subscriber level or above. Incorrect authorization means a permission check exists but evaluates the wrong thing, so it passes for callers it was meant to stop.

The action runs for users the code intended to exclude, with the same effect as having no check at all. For BlockSpare the fix is 5.0.0: builds <= 4.2.6 are affected, anything from 5.0.0 onward is not.

Remediation

Update to version 5.0.0, or a newer patched version

How does WordSec protect against this?

Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: BlockSpare 5.0.0 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-1242https://www.wordfence.com/threat-intel/vulnerabilities/id/2e1bbaa2-5bb3-442e-b4a8-96db98500e7bhttps://nvd.nist.gov/vuln/detail/CVE-2026-1242

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C