CVE-2021-24236: The Imagements WordPress plugin through 1.2.5 allows images to be uploaded in comments, however only checks for the Content-Type in the request to forbid…

PriorityP273critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EXPLOIT

EPSS

7.14%

93.5th percentile

The Imagements WordPress plugin through 1.2.5 allows images to be uploaded in comments, however only checks for the Content-Type in the request to forbid dangerous files. This allows unauthenticated attackers to upload arbitrary files by using a valid image Content-Type along with a PHP filename and code, leading to RCE.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
imagements_project	imagements	<= 1.2.5	—
williewonka	imagements	1.2.5 – 1.2.5	—

Detection & IOCsextracted from sources · hover to see the quote

path/wp-content/plugins/imagements/images/

→Unauthenticated file upload via comment submission: attacker sends a PHP file with a valid image Content-Type header. Detect multipart POST requests to the comment endpoint where Content-Type claims an image type but the uploaded filename has a .php (or similar executable) extension. ↗
→Monitor HTTP GET requests to /wp-content/plugins/imagements/images/ for PHP file execution — successful exploitation results in a web-accessible PHP shell under this path.
→Look for multipart form-data POST requests containing the WebKit boundary 'WebKitFormBoundaryIYl2Oz8ptq5OMtbU' as a specific exploit-tool fingerprint in HTTP traffic.

·The plugin only checks the Content-Type header (not the actual file content or extension) to block dangerous uploads, so any valid image MIME type (e.g. image/jpeg) paired with a .php filename bypasses the control entirely. ↗
·Exploitation requires no authentication — the vulnerable upload vector is exposed through the public comment submission form. ↗

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P

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