CVE-2026-9227 GutenBee <= 2.20.1 - Authenticated (Author+) Arbitrary File Upload via wp_check_filetype_and_ext Filter
Authenticated attackers with author privileges can upload executable files via double-extension bypass, leading to remote code execution.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-9227?
CVE-2026-9227 is a high-severity vulnerability in cssigniterteam GutenBee – Gutenberg Blocks, published on 28 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-434
Which versions are affected by CVE-2026-9227?
How do I fix CVE-2026-9227?
No fix has been published for CVE-2026-9227 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-9227 being exploited?
There is no known exploitation of CVE-2026-9227 in the wild and no public exploit code.
Sources
Also known as GHSA-fxjg-wrwj-m45j.