Null pointer exception error when deploying at production server

I have deployed shinyproxy on a production server it seems to work fine. However, in the shinyproxy logs I frequently get the null pointer exception error as shown on the bottom of this post. Is this an issue in ShinyProxy? Or is this due to incorrect configuration from our part?

this is the server part of our application.yaml:

server:
  forward-headers-strategy: native
  frame-options: sameorigin
  secure-cookies: true
  same-site-cookie: Lax

We are using the shinyproxy docker image (with shinyproxy v3.1.1) with openID connect for authentication. We enforce https, and the application is deployed behind a NGINX reverse proxy.

Error message:

2024-09-20T12:22:21.683Z ERROR 1 --- [XNIO-1 task-7] io.undertow.request                      : UT005023: Exception handling request to /cyberscan/.html

java.lang.NullPointerException: Cannot invoke "String.contains(java.lang.CharSequence)" because the return value of "jakarta.servlet.http.HttpServletRequest.getHeader(String)" is null
        at eu.openanalytics.containerproxy.security.UserAgentFilter.doFilterInternal(UserAgentFilter.java:36) ~[containerproxy-1.1.1.jar!/:1.1.1]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at eu.openanalytics.containerproxy.util.AppRecoveryFilter.doFilter(AppRecoveryFilter.java:63) ~[containerproxy-1.1.1.jar!/:1.1.1]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilterInternal(BasicAuthenticationFilter.java:181) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at eu.openanalytics.containerproxy.auth.impl.oidc.OpenIdReAuthorizeFilter.doFilterInternal(OpenIdReAuthorizeFilter.java:133) ~[containerproxy-1.1.1.jar!/:1.1.1]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:221) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:221) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.oauth2.client.web.OAuth2AuthorizationRequestRedirectFilter.doFilterInternal(OAuth2AuthorizationRequestRedirectFilter.java:181) ~[spring-security-oauth2-client-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:107) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:93) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.csrf.CsrfFilter.doFilterInternal(CsrfFilter.java:117) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:91) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:90) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:75) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.context.SecurityContextHolderFilter.doFilter(SecurityContextHolderFilter.java:82) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.context.SecurityContextHolderFilter.doFilter(SecurityContextHolderFilter.java:69) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:62) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.session.ForceEagerSessionCreationFilter.doFilterInternal(ForceEagerSessionCreationFilter.java:45) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:227) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.session.DisableEncodeUrlFilter.doFilterInternal(DisableEncodeUrlFilter.java:42) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.wrapFilter(ObservationFilterChainDecorator.java:240) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$AroundFilterObservation$SimpleAroundFilterObservation.lambda$wrap$0(ObservationFilterChainDecorator.java:323) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$ObservationFilter.doFilter(ObservationFilterChainDecorator.java:224) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.ObservationFilterChainDecorator$VirtualFilterChain.doFilter(ObservationFilterChainDecorator.java:137) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:233) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:191) ~[spring-security-web-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:113) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.web.servlet.handler.HandlerMappingIntrospector.lambda$createCacheFilter$3(HandlerMappingIntrospector.java:195) ~[spring-webmvc-6.1.8.jar!/:6.1.8]
        at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:113) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.web.filter.CompositeFilter.doFilter(CompositeFilter.java:74) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.security.config.annotation.web.configuration.WebMvcSecurityConfiguration$CompositeFilterChainProxy.doFilter(WebMvcSecurityConfiguration.java:230) ~[spring-security-config-6.2.4.jar!/:6.2.4]
        at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:352) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:268) ~[spring-web-6.1.8.jar!/:6.1.8]
        at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:67) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:67) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at org.springframework.web.filter.ServerHttpObservationFilter.doFilterInternal(ServerHttpObservationFilter.java:109) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:67) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-6.1.8.jar!/:6.1.8]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.8.jar!/:6.1.8]
        at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:67) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:84) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.ServletChain$1.handleRequest(ServletChain.java:68) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.server.handlers.PathHandler.handleRequest(PathHandler.java:104) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at eu.openanalytics.containerproxy.util.ProxyMappingManager$ProxyPathHandler.handleRequest(ProxyMappingManager.java:325) ~[containerproxy-1.1.1.jar!/:1.1.1]
        at io.undertow.servlet.handlers.RedirectDirHandler.handleRequest(RedirectDirHandler.java:68) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:117) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.server.handlers.SameSiteCookieHandler.handleRequest(SameSiteCookieHandler.java:97) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.SendErrorPageHandler.handleRequest(SendErrorPageHandler.java:52) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:276) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:132) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:256) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:101) ~[undertow-servlet-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.server.Connectors.executeRootHandler(Connectors.java:393) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:859) ~[undertow-core-2.3.13.Final.jar!/:2.3.13.Final]
        at org.jboss.threads.ContextHandler$1.runWith(ContextHandler.java:18) ~[jboss-threads-3.5.0.Final.jar!/:3.5.0.Final]
        at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2513) ~[jboss-threads-3.5.0.Final.jar!/:3.5.0.Final]
        at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1538) ~[jboss-threads-3.5.0.Final.jar!/:3.5.0.Final]
        at org.xnio.XnioWorker$WorkerThreadFactory$1$1.run(XnioWorker.java:1282) ~[xnio-api-3.8.8.Final.jar!/:3.8.8.Final]
        at java.base/java.lang.Thread.run(Thread.java:840) ~[na:na]

May you share the nginx conf ?