🔐 CVE Alert

CVE-2026-9227

HIGH 8.8

GutenBee <= 2.20.1 - Authenticated (Author+) Arbitrary File Upload via wp_check_filetype_and_ext Filter

CVSS Score
8.8
EPSS Score
0.0%
EPSS Percentile
0th

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.

CWE CWE-434
Vendor cssigniterteam
Product gutenbee – gutenberg blocks
Published May 28, 2026
Last Updated May 28, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability

Affected Versions

cssigniterteam / GutenBee – Gutenberg Blocks
0 ≤ 2.20.1

References

NVD ↗ CVE.org ↗ EPSS Data ↗
wordfence.com: https://www.wordfence.com/threat-intel/vulnerabilities/id/2d20e8c9-975d-4e8c-8bea-50935853c7d4?source=cve plugins.trac.wordpress.org: https://plugins.trac.wordpress.org/browser/gutenbee/tags/2.20.1/gutenbee.php#L571 plugins.trac.wordpress.org: https://plugins.trac.wordpress.org/browser/gutenbee/tags/2.20.1/gutenbee.php#L570 plugins.trac.wordpress.org: https://plugins.trac.wordpress.org/browser/gutenbee/tags/2.20.1/gutenbee.php#L579 plugins.trac.wordpress.org: https://plugins.trac.wordpress.org/browser/gutenbee/tags/2.20.0/gutenbee.php#L571 plugins.trac.wordpress.org: https://plugins.trac.wordpress.org/browser/gutenbee/tags/2.20.0/gutenbee.php#L570 plugins.trac.wordpress.org: https://plugins.trac.wordpress.org/browser/gutenbee/tags/2.20.0/gutenbee.php#L579 github.com: https://github.com/cssigniter/gutenbee/commit/bde934cdecf67a4de1d6548cc1fc6c59bc6690e5 plugins.trac.wordpress.org: https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3543574%40gutenbee&new=3543574%40gutenbee&sfp_email=&sfph_mail=

Credits

Athiwat Tiprasaharn