Sequelize is a Node.js ORM tool. Prior to 6.37.8, there is SQL injection via unescaped cast type in JSON/JSONB where clause processing. The _traverseJSON() function splits JSON path keys on :: to extract a cast type, which is interpolated raw into CAST(... AS <type>) SQL. An attacker who controls JSON object keys can inject arbitrary SQL and exfiltrate data from any table. This vulnerability is fixed in 6.37.8.