Vulnerability record · CVE-2026-9227 · published 28 May 2026
CVE-2026-9227: Unrestricted file upload vulnerability
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.
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
References
Track CVE-2026-9227 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-9227), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.
