diff --git a/extensions/websockets-next/server/deployment/src/main/java/io/quarkus/websockets/next/deployment/WebSocketServerProcessor.java b/extensions/websockets-next/server/deployment/src/main/java/io/quarkus/websockets/next/deployment/WebSocketServerProcessor.java
index fecdd74c0606a..eba1598a6eb6f 100644
--- a/extensions/websockets-next/server/deployment/src/main/java/io/quarkus/websockets/next/deployment/WebSocketServerProcessor.java
+++ b/extensions/websockets-next/server/deployment/src/main/java/io/quarkus/websockets/next/deployment/WebSocketServerProcessor.java
@@ -82,6 +82,7 @@ public class WebSocketServerProcessor {
     static final String ENDPOINT_SUFFIX = "_WebSocketEndpoint";
     static final String NESTED_SEPARATOR = "$_";
 
+    // Parameter names consist of alphanumeric characters and underscore
     private static final Pattern PATH_PARAM_PATTERN = Pattern.compile("\\{[a-zA-Z0-9_]+\\}");
 
     @BuildStep
@@ -240,6 +241,14 @@ static String getPath(String path) {
         while (m.find()) {
             // Replace {foo} with :foo
             String match = m.group();
+            int end = m.end();
+            if (end < path.length()) {
+                char nextChar = path.charAt(end);
+                if (Character.isAlphabetic(nextChar) || Character.isDigit(nextChar) || nextChar == '_') {
+                    throw new WebSocketServerException("Path parameter " + match
+                            + " may not be followed by an alphanumeric character or underscore: " + path);
+                }
+            }
             m.appendReplacement(sb, ":" + match.subSequence(1, match.length() - 1));
         }
         m.appendTail(sb);
diff --git a/extensions/websockets-next/server/deployment/src/test/java/io/quarkus/websockets/next/deployment/WebSocketServerProcessorTest.java b/extensions/websockets-next/server/deployment/src/test/java/io/quarkus/websockets/next/deployment/WebSocketServerProcessorTest.java
index 6c774f82c21ce..44e37dc73011d 100644
--- a/extensions/websockets-next/server/deployment/src/test/java/io/quarkus/websockets/next/deployment/WebSocketServerProcessorTest.java
+++ b/extensions/websockets-next/server/deployment/src/test/java/io/quarkus/websockets/next/deployment/WebSocketServerProcessorTest.java
@@ -1,18 +1,35 @@
 package io.quarkus.websockets.next.deployment;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import org.junit.jupiter.api.Test;
 
+import io.quarkus.websockets.next.WebSocketServerException;
+
 public class WebSocketServerProcessorTest {
 
     @Test
     public void testGetPath() {
         assertEquals("/foo/:id", WebSocketServerProcessor.getPath("/foo/{id}"));
+        assertEquals("/foo/:id/bar/:id2", WebSocketServerProcessor.getPath("/foo/{id}/bar/{id2}"));
         assertEquals("/foo/:bar-:baz", WebSocketServerProcessor.getPath("/foo/{bar}-{baz}"));
         assertEquals("/ws/v:version", WebSocketServerProcessor.getPath("/ws/v{version}"));
-        assertEquals("/foo/v:bar/:bazand:alpha_1-:name",
-                WebSocketServerProcessor.getPath("/foo/v{bar}/{baz}and{alpha_1}-{name}"));
+        WebSocketServerException e = assertThrows(WebSocketServerException.class,
+                () -> WebSocketServerProcessor.getPath("/foo/v{bar}/{baz}and{alpha_1}-{name}"));
+        assertEquals(
+                "Path parameter {baz} may not be followed by an alphanumeric character or underscore: /foo/v{bar}/{baz}and{alpha_1}-{name}",
+                e.getMessage());
+        e = assertThrows(WebSocketServerException.class,
+                () -> WebSocketServerProcessor.getPath("/foo/v{bar}/{baz}_{alpha_1}-{name}"));
+        assertEquals(
+                "Path parameter {baz} may not be followed by an alphanumeric character or underscore: /foo/v{bar}/{baz}_{alpha_1}-{name}",
+                e.getMessage());
+        e = assertThrows(WebSocketServerException.class,
+                () -> WebSocketServerProcessor.getPath("/foo/v{bar}/{baz}1-{name}"));
+        assertEquals(
+                "Path parameter {baz} may not be followed by an alphanumeric character or underscore: /foo/v{bar}/{baz}1-{name}",
+                e.getMessage());
     }
 
     @Test
diff --git a/extensions/websockets-next/server/deployment/src/test/java/io/quarkus/websockets/next/test/endpoints/InvalidPathParamTest.java b/extensions/websockets-next/server/deployment/src/test/java/io/quarkus/websockets/next/test/endpoints/InvalidPathParamTest.java
new file mode 100644
index 0000000000000..264e01f5b01dc
--- /dev/null
+++ b/extensions/websockets-next/server/deployment/src/test/java/io/quarkus/websockets/next/test/endpoints/InvalidPathParamTest.java
@@ -0,0 +1,36 @@
+package io.quarkus.websockets.next.test.endpoints;
+
+import static org.junit.jupiter.api.Assertions.fail;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.quarkus.test.QuarkusUnitTest;
+import io.quarkus.websockets.next.OnOpen;
+import io.quarkus.websockets.next.WebSocket;
+import io.quarkus.websockets.next.WebSocketServerException;
+
+public class InvalidPathParamTest {
+
+    @RegisterExtension
+    public static final QuarkusUnitTest test = new QuarkusUnitTest()
+            .withApplicationRoot(root -> {
+                root.addClasses(InvalidPathParam.class);
+            })
+            .setExpectedException(WebSocketServerException.class);
+
+    @Test
+    void testInvalidPathParam() {
+        fail();
+    }
+
+    @WebSocket(path = "/service/{invalid}_{param}")
+    public static class InvalidPathParam {
+
+        @OnOpen
+        public void onOpen() {
+        }
+
+    }
+
+}