CVE-2026-5478

CVE-2026-5478: high vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2026-5478CVSS 8.1Web

CVE-2026-5478

CVE-2026-5478: high vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
8.1 HIGH
EPSS
59.92%
Known exploited
not in KEV
Product
-

What is known

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.

Business impact

Successful exploitation of CVE-2026-5478, a high vulnerability (CVSS 8.1) affecting the affected product, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether the affected product is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

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