CVE-2026-4030: Arbitrary File Access in Database Backup for WordPress

The impact of CVE-2026-4030 is significant, particularly within WordPress Multisite environments. An attacker exploiting this vulnerability can gain unauthorized access to sensitive files, including configuration files, database credentials, and potentially even source code. Successful exploitation could lead to the disclosure of confidential data, modification of website content, or even complete site takeover. The ability to delete arbitrary files further exacerbates the risk, potentially disrupting website operations and causing data loss. This vulnerability shares similarities with other file access vulnerabilities where improper authorization checks allow attackers to bypass security controls.

1. 予約済み2026-03-12
2. 公開日2026-05-13
3. 更新日2026-05-14

The primary mitigation for CVE-2026-4030 is to immediately upgrade the Database Backup for WordPress plugin to version 2.5.3 or later. If upgrading is not immediately feasible due to compatibility issues or breaking changes, consider implementing a temporary workaround by restricting access to the plugin's backup directory. This can be achieved through file system permissions or web server configuration. While not a complete solution, this can limit the attacker's ability to read or delete files. Monitor WordPress logs for any unusual file access attempts, particularly those originating from unauthenticated users. After upgrading, verify the fix by attempting to access a non-public file through the plugin's interface; access should be denied.