CVE-2022-21700: Micronaut is a JVM-based, full stack Java framework designed for building JVM web applications with support for Java, Kotlin and the Groovy language.

Micronaut is a JVM-based, full stack Java framework designed for building JVM web applications with support for Java, Kotlin and the Groovy language.

Micronaut is a JVM-based, full stack Java framework designed for building JVM web applications with support for Java, Kotlin and the Groovy language. In affected versions sending an invalid Content Type header leads to memory leak in DefaultArgumentConversionContext as this type is erroneously used in static state. ### Impact Sending an invalid Content Type header leads to memory leak in `DefaultArgumentConversionContext` as this type is erroneously used in static state. ### Patches The problem is patched in Micronaut 3.2.7 and above. ### Workarounds The default content type binder can be replaced in an existing Micronaut application to mitigate the issue: ```java package example; import java.util.List; import io.micronaut.context.annotation.Replaces; import io.micronaut.core.convert.ConversionService; import io.micronaut.http.MediaType; import io.micronaut.http.bind.DefaultRequestBinderRegistry; import io.micronaut.http.bind.binders.RequestArgumentBinder; import jakarta.inject.Singleton; @Singleton @Replaces(DefaultRequestBinderRegistry.class) class FixedRequestBinderRegistry extends DefaultRequestBinderRegistry { public FixedRequestBinderRegistry(ConversionService conversionServi

Description from the National Vulnerability Database, published by GitHub

What it means for a small business

If your business uses micronaut-core, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 1.1%, higher than 66% of CVEs. That’s above average: worth scheduling this week. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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