Vulnerability record · CVE-2026-9834 · published 2 July 2026
CVE-2026-9834: Command injection vulnerability
The WP Database Backup – Unlimited Database & Files Backup by Backup for WP plugin for WordPress is vulnerable to OS Command Injection in all versions up to and including 7.11 via the `wp_db_exclude_table` parameter. This is due to the direct concatenation of user-supplied `$_POST['wp_db_exclude_table']` values into the `mysqldump` shell command string in the `mysqldump()` function of `includes/admin/class-wpdb-admin.php` without wrapping them in `escapeshellarg()`—every other argument in the same command (DB_USER, DB_PASSWORD, host, filename, DB_NAME) is properly escaped, making the exclude-table values the sole exception—and because the only applied filtering, `sanitize_text_field()` via `recursive_sanitize_text_field()`, strips HTML tags but leaves shell metacharacters such as `;`, `|`, `` ` ``, and `$()` intact. This makes it possible for authenticated attackers, with administrator-level access and above, to execute arbitrary operating system commands on the server, potentially enabling full remote code execution. The injection is stored: malicious values submitted through the plugin settings form are persisted to the WordPress options table via `update_option('wp_db_exclude_table')` and later retrieved with `get_option()` and passed unsanitized to `shell_exec()` whenever a backup operation runs.
Description
The WP Database Backup – Unlimited Database & Files Backup by Backup for WP plugin for WordPress is vulnerable to OS Command Injection in all versions up to and including 7.11 via the `wp_db_exclude_table` parameter. This is due to the direct concatenation of user-supplied `$_POST['wp_db_exclude_table']` values into the `mysqldump` shell command string in the `mysqldump()` function of `includes/admin/class-wpdb-admin.php` without wrapping them in `escapeshellarg()`—every other argument in the same command (DB_USER, DB_PASSWORD, host, filename, DB_NAME) is properly escaped, making the exclude-table values the sole exception—and because the only applied filtering, `sanitize_text_field()` via `recursive_sanitize_text_field()`, strips HTML tags but leaves shell metacharacters such as `;`, `|`, `` ` ``, and `$()` intact. This makes it possible for authenticated attackers, with administrator-level access and above, to execute arbitrary operating system commands on the server, potentially enabling full remote code execution. The injection is stored: malicious values submitted through the plugin settings form are persisted to the WordPress options table via `update_option('wp_db_exclude_table')` and later retrieved with `get_option()` and passed unsanitized to `shell_exec()` whenever a backup operation runs.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
References
Track CVE-2026-9834 inside VULONE
Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.
Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-9834), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.
