CVE-2026-27886

Strapi is an open source headless content management system. Strapi versions starting in 4.0.0 and prior to 5.37.0 did not sufficiently sanitize query parameters when filtering content via relational fields. An unauthenticated attacker could use the where query parameter on any publicly-accessible content-type with an updatedBy (or other admin-relation) field to perform a boolean-oracle attack against private fields on the joined admin_users table, including the resetPasswordToken field. Extracting an admin reset token via this oracle made full administrative account takeover possible without authentication. When a filter such as where[updatedBy][resetPasswordToken][$startsWith]=a was applied to a public Content API endpoint, the underlying query generation performed a LEFT JOIN against the admin_users table and emitted a WHERE clause referencing the joined column. The query parameter sanitization layer did not block operator chains that traversed into relational target schemas the caller had no read permission on, allowing the response count to be used as a one-bit oracle on any admin-table field. The patch in version 5.37.0 introduces explicit query-parameter sanitization at the controller and service boundary via three new primitives: strictParam, addQueryParams, and addBodyParams. Operator chains that traverse into restricted relational targets are now rejected before reaching the database.