## cve-2026-47856 - MEDIUM - JsonToObjectTransformer resolves the json__TypeId__ message header to an arbitrary class without an allow-list

- 種別: advisory
- 関連技術: spring, java
- CVE: CVE-2026-47856
- 公開日時: 2026-08-20T00:00:00.000Z
- 情報源: Spring Security Advisories (https://spring.io/security/cve-2026-47856)
- パーマリンク: https://vulnpulse.app/items/spring-security-b4051a3f0fc8

Spring Integration's JSON to object conversion uses the json__TypeId__ header to choose the deserialization target type, and resolves that header value to a class with ClassUtils.forName and no type/package allow-list. When the header originates from an external producer (it is mapped from the inbound transport, e.g. AMQP/Kafka, into the message), an attacker controls which class the framework loads and which type the JSON payload is bound into.