diff --git a/web/src/main/java/org/springframework/security/web/server/WebFilterChainProxy.java b/web/src/main/java/org/springframework/security/web/server/WebFilterChainProxy.java
index 1dfc31f2d1..94df035179 100644
--- a/web/src/main/java/org/springframework/security/web/server/WebFilterChainProxy.java
+++ b/web/src/main/java/org/springframework/security/web/server/WebFilterChainProxy.java
@@ -44,6 +44,7 @@ public class WebFilterChainProxy implements WebFilter {
 		return filters
 				.filterWhen( securityWebFilterChain -> securityWebFilterChain.matches(exchange))
 				.next()
+				.switchIfEmpty(chain.filter(exchange).then(Mono.empty()))
 				.flatMap( securityWebFilterChain -> securityWebFilterChain.getWebFilters()
 					.collectList()
 				)
diff --git a/web/src/test/java/org/springframework/security/web/server/WebFilterChainProxyTests.java b/web/src/test/java/org/springframework/security/web/server/WebFilterChainProxyTests.java
new file mode 100644
index 0000000000..4236d2445d
--- /dev/null
+++ b/web/src/test/java/org/springframework/security/web/server/WebFilterChainProxyTests.java
@@ -0,0 +1,60 @@
+/*
+ * Copyright 2002-2017 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.security.web.server;
+
+import org.junit.Test;
+import org.springframework.http.HttpStatus;
+import org.springframework.security.web.server.util.matcher.ServerWebExchangeMatcher;
+import org.springframework.security.web.server.util.matcher.ServerWebExchangeMatcher.MatchResult;
+import org.springframework.test.web.reactive.server.WebTestClient;
+import org.springframework.web.server.ServerWebExchange;
+import org.springframework.web.server.WebFilter;
+import org.springframework.web.server.WebFilterChain;
+import reactor.core.publisher.Mono;
+
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * @author Rob Winch
+ * @since 5.0
+ */
+
+public class WebFilterChainProxyTests {
+
+	// gh-4668
+	@Test
+	public void filterWhenNoMatchThenContinuesChainAnd404() {
+		List<WebFilter> filters = Arrays.asList(new Http200WebFilter());
+		ServerWebExchangeMatcher notMatch = exchange -> MatchResult.notMatch();
+		MatcherSecurityWebFilterChain chain = new MatcherSecurityWebFilterChain(notMatch, filters);
+		WebFilterChainProxy filter = WebFilterChainProxy.fromSecurityWebFilterChains(chain);
+
+		WebTestClient.bindToController(new Object()).webFilter(filter).build()
+			.get()
+			.exchange()
+			.expectStatus().isNotFound();
+	}
+
+	static class Http200WebFilter implements WebFilter {
+		@Override
+		public Mono<Void> filter(ServerWebExchange exchange,
+			WebFilterChain chain) {
+			return Mono.fromRunnable(() -> exchange.getResponse().setStatusCode(HttpStatus.FORBIDDEN));
+		}
+	}
+}