--- title: JsonToObjectTransformer resolves the json__TypeId__... description: A CVE affecting Spring Integration's JsonToObjectTransformer describes how the json__TypeId__ message header can be used to resolve an arbitrary class without... canonical: https://daily.dev/posts/jsontoobjecttransformer-resolves-the-json-typeid-message-header-to-an-arbitrary-class-without-an--pnqdqqjdm twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: JsonToObjectTransformer resolves the json__TypeId__ message header to an arbitrary class without an allow-list | daily.dev og:description: A CVE affecting Spring Integration's JsonToObjectTransformer describes how the json__TypeId__ message header can be used to resolve an arbitrary class without... og:url: https://daily.dev/posts/jsontoobjecttransformer-resolves-the-json-typeid-message-header-to-an-arbitrary-class-without-an--pnqdqqjdm og:image: https://api.daily.dev/og/posts/PNqDqQjdm.png og:image:alt: JsonToObjectTransformer resolves the json__TypeId__ message header to an arbitrary class without an allow-list og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # JsonToObjectTransformer resolves the json__TypeId__ message header to an arbitrary class without an allow-list **[Spring](https://daily.dev/sources/spring)** · 1 min read · 2 upvotes · 0 comments ## Summary A CVE affecting Spring Integration's JsonToObjectTransformer describes how the json__TypeId__ message header can be used to resolve an arbitrary class without an allow-list, creating a potential deserialization vulnerability. The page itself is largely obscured by cookie consent boilerplate, with minimal technical detail beyond the advisory title. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is the security issue with JsonToObjectTransformer in Spring Integration? JsonToObjectTransformer resolves the json__TypeId__ message header to an arbitrary class without checking it against an allow-list, which can let an attacker influence which class gets instantiated during JSON deserialization. This is tracked as a CVE affecting Spring Integration and stems from the lack of type restriction on the header value. _Track Spring Integration security advisories on daily.dev before patching deserialization risks in production._ ## Similar posts on daily.dev - [Unsafe Java deserialization in SerializingHttpMessageConverter — remote code execution](https://daily.dev/posts/unsafe-java-deserialization-in-serializinghttpmessageconverter-remote-code-execution-wisjbrluv) · Spring · 7 upvotes · 0 comments - [Fastjson 2.x Remote Code Execution Vulnerability Notice](https://daily.dev/posts/fastjson-2-x-remote-code-execution-vulnerability-notice-qj1f3nati) · Security Boulevard · 0 upvotes · 0 comments - [EmbeddedHeadersJsonMessageMapper default gives wire peer full control of MessageHeaders](https://daily.dev/posts/embeddedheadersjsonmessagemapper-default-gives-wire-peer-full-control-of-messageheaders-pxcmbfa2r) · Spring · 3 upvotes · 0 comments - [Deserialization allow-list silently bypassed: setBeanClassLoader replaces deserializer but mapper keeps stale reference](https://daily.dev/posts/deserialization-allow-list-silently-bypassed-setbeanclassloader-replaces-deserializer-but-mapper-ke-cxhvfsc6w) · Spring · 9 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security), [#java](https://daily.dev/tags/java), [#spring](https://daily.dev/tags/spring) [View this post on daily.dev](https://daily.dev/posts/jsontoobjecttransformer-resolves-the-json-typeid-message-header-to-an-arbitrary-class-without-an--pnqdqqjdm) ```json 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