CVE-2026-5293

What is known

The 診断ジェネレータ作成プラグイン (Diagnosis Generator) plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'js' parameter in versions up to and including 1.4.16. This is due to missing authorization checks and insufficient input sanitization in the themeFunc() function. The function is hooked to 'admin_init' and processes theme update requests without verifying user capabilities, allowing any authenticated user (including subscribers) to save malicious JavaScript to theme files. Additionally, the save() function uses stripslashes() which removes WordPress's magic quotes protection. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in theme files that will execute whenever a user accesses a page containing the diagnosis form shortcode.

Business impact

Successful exploitation of CVE-2026-5293, a medium vulnerability (CVSS 6.4) 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

• NVD
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