CVE-2026-5478: The Everest Forms plugin for WordPress is vulnerable to Arbitrary File Read and Deletion in all versions up to, and including, 3.4.4. This is due to t...

Description

The Everest Forms plugin for WordPress is vulnerable to Arbitrary File Read and Deletion in all versions up to, and including, 3.4.4. This is due to the plugin trusting attacker-controlled old_files data from public form submissions as legitimate server-side upload state, and converting attacker-supplied URLs into local filesystem paths using regex-based string replacement without canonicalization or directory boundary enforcement. This makes it possible for unauthenticated attackers to read arbitrary local files (e.g., wp-config.php) by injecting path-traversal payloads into the old_files upload field parameter, which are then attached to notification emails. The same path resolution is also used in the post-email cleanup routine, which calls unlink() on the resolved path, resulting in the targeted file being deleted after being attached. This can lead to full site compromise through disclosure of database credentials and authentication salts from wp-config.php, and denial of service through deletion of critical files. Prerequisite: The form must contain a file-upload or image-upload field, and disable storing entry information.

Metrics

CVSS 3.1

8.1/10

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

EPSS Probability

1.02%

59.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-22

References

Timeline

Published: Apr 20, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-5478?

The Everest Forms plugin for WordPress is vulnerable to Arbitrary File Read and Deletion in all versions up to, and including, 3.4.4. This is due to the plugin trusting attacker-controlled old_files data from public form submissions as legitimate server-side upload state, and converting attacker-supplied URLs into local filesystem paths using regex-based string replacement without canonicalization or directory boundary enforcement. This makes it possible for unauthenticated attackers to read arbitrary local files (e.g., wp-config.php) by injecting path-traversal payloads into the old_files upload field parameter, which are then attached to notification emails. The same path resolution is also used in the post-email cleanup routine, which calls unlink() on the resolved path, resulting in the targeted file being deleted after being attached. This can lead to full site compromise through disclosure of database credentials and authentication salts from wp-config.php, and denial of service through deletion of critical files. Prerequisite: The form must contain a file-upload or image-upload field, and disable storing entry information.

How severe is CVE-2026-5478?

CVE-2026-5478 has a CVSS score of 8.1/10 (HIGH severity). The EPSS model estimates a 1.02% probability of exploitation in the next 30 days.

How do I fix CVE-2026-5478?

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.