diff --git a/openvidu-server/pom.xml b/openvidu-server/pom.xml
index d69c4b49..ee86fd8b 100644
--- a/openvidu-server/pom.xml
+++ b/openvidu-server/pom.xml
@@ -187,6 +187,11 @@
 					<groupId>org.springframework</groupId>
 					<artifactId>spring-websocket</artifactId>
 				</exclusion>
+				<exclusion>
+					<!-- Until kurento-java spring-boot dependency is updated to 2.2.4.RELEASE -->
+					<groupId>org.apache.tomcat.embed</groupId>
+					<artifactId>tomcat-embed-websocket</artifactId>
+				</exclusion>
 				<exclusion>
 					<groupId>org.slf4j</groupId>
 					<artifactId>slf4j-api</artifactId>
diff --git a/openvidu-server/src/main/java/io/openvidu/server/utils/FormatChecker.java b/openvidu-server/src/main/java/io/openvidu/server/utils/FormatChecker.java
index ced8c8ea..05748411 100644
--- a/openvidu-server/src/main/java/io/openvidu/server/utils/FormatChecker.java
+++ b/openvidu-server/src/main/java/io/openvidu/server/utils/FormatChecker.java
@@ -31,7 +31,7 @@ public class FormatChecker {
 
 	public boolean isValidCustomSessionId(String customSessionId) {
 		// Alphanumeric string
-		return customSessionId.matches("[a-zA-Z0-9]+");
+		return customSessionId.matches("[a-zA-Z0-9_-]+");
 	}
 
 }