WebFlux handles requests with an illegal Host header inconsistently [SPR-16778]

[spring-projects-issues]

Andy Wilkinson opened SPR-16778 and commented

The various request adapters in WebFlux do not all handle a request with an illegal Host header in the same way. ReactorHttpHandlerAdapter catches a URISyntaxException and maps it to a 400 response. UndertowHttpHandlerAdapter and ServletHttpHandlerAdapter do not catch URISyntaxException which results in a 500 response.

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Affects: 5.0.5

Reference URL: spring-projects/spring-boot#12987

Issue Links:

• DDoS Spring 5 RouterFunction apps [SPR-15560] #20119 DDoS Spring 5 RouterFunction apps

Referenced from: commits b0aa08a, 8d157cb