CVE-2026-9227

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

Published May 28, 2026 CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Cssigniterteam
Cssigniterteam gutenbee – Gutenberg Blocks
Wordpress
Wordpress wordpress
Vendors & Products Cssigniterteam
Cssigniterteam gutenbee – Gutenberg Blocks
Wordpress
Wordpress wordpress
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title GutenBee <= 2.20.1 - Authenticated (Author+) Arbitrary File Upload via wp_check_filetype_and_ext Filter
Weaknesses CWE-434
References
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Wordfence
Published
Updated
May 28, 2026, 10:35 AM
Reserved
May 21, 2026, 6:32 PM
Status
Deferred
Published
May 28, 2026, 8:16 AM
Modified
Jun 17, 2026, 11:04 AM