CVE-2026-126537 Path traversal in Ninja Forms - File Uploads
Unauthenticated attackers can delete arbitrary server files, such as wp-config.php, enabling WordPress site takeover; sites using Ninja Forms File Uploads should care.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Harmful if only installed
- No
- Needs a specific call
- No
- Fix
- None listed
What is CVE-2026-126537?
CVE-2026-126537 is a critical path traversal vulnerability in SaturdayDrive Ninja Forms - File Uploads, published on 11 Nov 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The Ninja Forms - File Uploads add-on for WordPress is vulnerable to Arbitrary File Deletion (and arbitrary file read via S3/Dropbox/Google Drive exfiltration) in versions up to, and including, 3.3.36. The flaw spans NF_FU_Fields_Upload::process() in includes/fields/upload.php — which returns early (leaving the client-supplied files[] intact) whenever a public submission carries a nonempty extra.saveProgress — and NF_FU_External_Abstracts_Service::process_upload() in includes/external/abstracts/service.php, whose authoritative-path reload only fires when the client sends upload_id. By omitting upload_id, an attacker's data[file_path] survives into the Background Upload queue and is used by both upload_file_to_s3() (as SourceFile) and the maybe_delete_server_file() unlink() call in includes/external/abstracts/backgroundupload.php, with no canonicalization or upload-directory containment check (the plugin's own is_path_within_upload_dir() helper is only applied on admin paths). This makes it possible for unauthenticated attackers to delete arbitrary files on the affected site's server which may make remote code execution possible — specifically, deleting wp-config.php forces WordPress into its setup screen, enabling full site takeover.
Weakness: CWE-22
Which versions are affected by CVE-2026-126537?
An affected version is exposed as installed. No special setting or call is needed.
How do I fix CVE-2026-126537?
No fix has been published for CVE-2026-126537 yet. Limit exposure of the affected software until one is available.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-126537 being exploited?
There is no known exploitation of CVE-2026-126537 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-rfc5-f6j6-9jgj.