CVE-2026-4373: The JetFormBuilder plugin for WordPress is vulnerable to arbitrary file read via path traversal in all versions up to, and including, 3.5.6.2. This is...

Description

The JetFormBuilder plugin for WordPress is vulnerable to arbitrary file read via path traversal in all versions up to, and including, 3.5.6.2. This is due to the 'Uploaded_File::set_from_array' method accepting user-supplied file paths from the Media Field preset JSON payload without validating that the path belongs to the WordPress uploads directory. Combined with an insufficient same-file check in 'File_Tools::is_same_file' that only compares basenames, this makes it possible for unauthenticated attackers to exfiltrate arbitrary local files as email attachments by submitting a crafted form request when the form is configured with a Media Field and a Send Email action with file attachment.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

0.40%

31.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-36

References

Timeline

Published: Mar 21, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-4373?

The JetFormBuilder plugin for WordPress is vulnerable to arbitrary file read via path traversal in all versions up to, and including, 3.5.6.2. This is due to the 'Uploaded_File::set_from_array' method accepting user-supplied file paths from the Media Field preset JSON payload without validating that the path belongs to the WordPress uploads directory. Combined with an insufficient same-file check in 'File_Tools::is_same_file' that only compares basenames, this makes it possible for unauthenticated attackers to exfiltrate arbitrary local files as email attachments by submitting a crafted form request when the form is configured with a Media Field and a Send Email action with file attachment.

How severe is CVE-2026-4373?

CVE-2026-4373 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.40% probability of exploitation in the next 30 days.

How do I fix CVE-2026-4373?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.