Fixed Jackson related security issue

Change-Id: I2053c14837683e419be705814631a3ffaad8a486
diff --git a/Changes b/Changes
index f8944ae..4dff93c 100644
--- a/Changes
+++ b/Changes
@@ -1,3 +1,7 @@
+0.31 2018-10-22
+    - [bugfix] Security upgrade of Jackson for CVE-2017-17485 and
+      CVE-2018-7489 (diewald)
+
 0.30 2018-07-31
     - Introduced docGroupRef and added VC reference in collection query (margaretha)
     - Fixed checking error in QuerySerializer (margaretha)
diff --git a/pom.xml b/pom.xml
index 4661e94..a78439e 100644
--- a/pom.xml
+++ b/pom.xml
@@ -4,7 +4,7 @@
 
 	<groupId>de.ids_mannheim.korap</groupId>
 	<artifactId>Koral</artifactId>
-	<version>0.30</version>
+	<version>0.31</version>
 	<packaging>jar</packaging>
 	<name>Koral</name>
 	<url>http://maven.apache.org</url>
@@ -36,7 +36,7 @@
 
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>		
-		<jackson.version>2.9.1</jackson.version>
+		<jackson.version>[2.9.5,)</jackson.version>
 		<java.version>1.8</java.version>
 	</properties>