CVE-2026-5436 MW WP Form <= 5.1.1 - Unauthenticated Arbitrary File Move via regenerate_upload_file_keys
Unauthenticated attackers can move arbitrary files, potentially leading to remote code execution, if specific form settings are enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-5436?
CVE-2026-5436 is a high-severity path traversal vulnerability in inc2734 MW WP Form, published on 8 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The MW WP Form plugin for WordPress is vulnerable to Arbitrary File Move/Read in all versions up to and including 5.1.1. This is due to insufficient validation of the $name parameter (upload field key) passed to the generate_user_file_dirpath() function, which uses WordPress's path_join() — a function that returns absolute paths unchanged, discarding the intended base directory. The attacker-controlled key is injected via the mwf_upload_files[] POST parameter, which is loaded into the plugin's Data model via _set_request_valiables(). During form processing, regenerate_upload_file_keys() iterates over these keys and calls generate_user_filepath() with the attacker-supplied key as the $name argument — the key survives validation because the targeted file (e.g., wp-config.php) genuinely exists at the absolute path. The _get_attachments() method then re-reads the same surviving keys and passes the resolved file path to move_temp_file_to_upload_dir(), which calls rename() to move the file into the uploads folder. This makes it possible for unauthenticated attackers to move arbitrary files on the server, which can easily lead to remote code execution when the right file is moved (such as wp-config.php). The vulnerability is only exploitable if a file upload field is added to the form and the “Saving inquiry data in database” option is enabled.
Weakness: CWE-22
Which versions are affected by CVE-2026-5436?
How do I fix CVE-2026-5436?
No fix has been published for CVE-2026-5436 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-2026-5436 being exploited?
There is no known exploitation of CVE-2026-5436 in the wild and no public exploit code.
Sources
Also known as GHSA-44gv-5x3q-67mm.