WordPress security changelog
HIGH CVE-2026-9227 Deferred

GutenBee – Gutenberg Blocks: Dangerous file upload

GutenBee – Gutenberg Blocks is affected by dangerous file upload. Exploitation requires at least author-level access. Successful exploitation can place attacker-controlled executable content on the server and may lead to full site compromise. The published affected range is <= 2.20.1.

CVE / CNA score 8.8 CVSS 3.1 · security@wordfence.com
NVD score Pending NVD has not published its own CVSS assessment.
Component
GutenBee – Gutenberg Blocks
Plugin slug
gutenbee
Affected
<= 2.20.1
Safe version
> 2.20.1
Published
May 28, 2026
Weakness
CWE-434 — Unrestricted Upload of File with Dangerous Type

This CVE was published May 28, 2026 and is one of 2 known issues for this plugin.

What to do

Update, patch or deactivate.

Update GutenBee – Gutenberg Blocks to a release after 2.20.1, or disable and remove it until a fixed version is available.

A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Source record

Technical description

The GutenBee – Gutenberg Blocks plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.20.1 via the gutenbee_file_and_ext_json function. This is due to a flawed strpos() substring check that only verifies whether the filename contains the string '.json' rather than confirming the filename ends with a .json extension, allowing double-extension filenames like shell.json.php to bypass validation. This makes it possible for authenticated attackers, with author-level access and above, to upload files that may be executable, which makes remote code execution possible.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References

Primary and upstream sources