CVE-2026-5478
CWE-22Published: April 20, 2026· Updated: Apr 22, 2026
Official 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.
Technical Analysis
CVE-2026-5478 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.1.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (5)
Quick Facts
Related CVEs (CWE-22)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-5478 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts