9.8Critical
CVE-2026-87796
The Multi Uploader for Gravity Forms plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 1.1.9 via the move_file function. This is due to insufficient file type validation during chunked upload handling. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 9.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Weakness
- CWE-434
- Assigned by
- security@wordfence.com
Dates
- Published
- 2026-09-17
- Last modified
- 2026-09-17
- Sources
- NVD
References
- https://plugins.trac.wordpress.org/browser/gf-multi-uploader/tags/1.1.9/GFMUAddon.class.php#L125
- https://plugins.trac.wordpress.org/browser/gf-multi-uploader/tags/1.1.9/inc/GFMUHandlePluploader.class.php#L257
- https://plugins.trac.wordpress.org/browser/gf-multi-uploader/tags/1.1.9/inc/GFMU_FileUploader.php#L319
- https://plugins.trac.wordpress.org/browser/gf-multi-uploader/tags/1.1.9/inc/GFMU_FileUploader.php#L322
- https://plugins.trac.wordpress.org/browser/gf-multi-uploader/tags/1.1.9/inc/GFMU_FileUploader.php#L560
- https://www.wordfence.com/threat-intel/vulnerabilities/id/47337bc1-fa3d-470c-9524-859295261017?source=cve