CVE-2026-6455: The WP Contact Form 7 DB Handler plugin for WordPress is vulnerable to Cross-Site Request Forgery leading to Arbitrary File Deletion via SQL Injection...

Description

The WP Contact Form 7 DB Handler plugin for WordPress is vulnerable to Cross-Site Request Forgery leading to Arbitrary File Deletion via SQL Injection and PHP Object Injection in versions up to and including 3.0. This is due to a missing nonce verification in the process_bulk_action() function, the nonce check is only executed when _wpnonce is present in the POST body, allowing it to be trivially bypassed by omitting the field, combined with the use of an unsanitized, unparameterized user-supplied value in a numeric SQL context (WHERE ID = $ID) and the unsafe deserialization of the query result's post_content field. An attacker can craft a CSRF page that tricks a logged-in administrator into triggering a UNION-based SQL injection payload (using CHAR() to avoid esc_sql quote-escaping) that returns a malicious serialized PHP array as post_content; upon deserialization, array values associated with keys containing 'ys_cfdbh_file' are used as file paths appended to the uploads directory path without any path traversal validation, and then passed to wp_delete_file(), allowing the attacker to delete arbitrary files on the server (e.g., wp-config.php, system files).

Metrics

CVSS 3.1

8.1/10

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

EPSS Probability

0.25%

15.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-352

References

Timeline

Published: May 28, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-6455?

The WP Contact Form 7 DB Handler plugin for WordPress is vulnerable to Cross-Site Request Forgery leading to Arbitrary File Deletion via SQL Injection and PHP Object Injection in versions up to and including 3.0. This is due to a missing nonce verification in the process_bulk_action() function, the nonce check is only executed when _wpnonce is present in the POST body, allowing it to be trivially bypassed by omitting the field, combined with the use of an unsanitized, unparameterized user-supplied value in a numeric SQL context (WHERE ID = $ID) and the unsafe deserialization of the query result's post_content field. An attacker can craft a CSRF page that tricks a logged-in administrator into triggering a UNION-based SQL injection payload (using CHAR() to avoid esc_sql quote-escaping) that returns a malicious serialized PHP array as post_content; upon deserialization, array values associated with keys containing 'ys_cfdbh_file' are used as file paths appended to the uploads directory path without any path traversal validation, and then passed to wp_delete_file(), allowing the attacker to delete arbitrary files on the server (e.g., wp-config.php, system files).

How severe is CVE-2026-6455?

CVE-2026-6455 has a CVSS score of 8.1/10 (HIGH severity). The EPSS model estimates a 0.25% probability of exploitation in the next 30 days.

How do I fix CVE-2026-6455?

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.