SQL Injection in Hiroaki-Miyashita Custom Field Template
CVE-2026-9855
The Custom Field Template plugin for WordPress is vulnerable to generic SQL Injection via the 'post_ID' parameter in all versions up to, and including, 2.7.8 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for authenticated attackers, with contributor-level access and above, to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database. The capability check via current_user_can('edit_post', $id) is bypassable because WordPress internally casts $id to an integer for the permission evaluation while the full unsanitized string is preserved and passed to the SQL sink, and a valid nonce — which is also required — can be legitimately obtained by any Contributor-level user from the post edit screen.
Vulnerability class: SQL Injection
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
Affected products
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-9855?
- CVE-2026-9855 is a medium-severity vulnerability in Hiroaki-Miyashita Custom Field Template, classified under SQL Injection. CVSS score: 6.5/10. Published 2026-09-19.
- How severe is CVE-2026-9855?
- Medium severity. CVSS v3 base score is 6.5 out of 10.