diff --git a/iis-common/pom.xml b/iis-common/pom.xml
index 8e8b786f9..1ec04d597 100644
--- a/iis-common/pom.xml
+++ b/iis-common/pom.xml
@@ -79,22 +79,22 @@
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-core_2.11</artifactId>
+            <artifactId>spark-core_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-sql_2.11</artifactId>
+            <artifactId>spark-sql_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-avro_2.11</artifactId>
+            <artifactId>spark-avro_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>pl.edu.icm.spark-utils</groupId>
-            <artifactId>spark-utils_2.11</artifactId>
+            <artifactId>spark-utils_2.12</artifactId>
         </dependency>
 
         <dependency>
diff --git a/iis-wf/iis-wf-affmatching/pom.xml b/iis-wf/iis-wf-affmatching/pom.xml
index b74b5e6a8..8ea3863e4 100644
--- a/iis-wf/iis-wf-affmatching/pom.xml
+++ b/iis-wf/iis-wf-affmatching/pom.xml
@@ -35,17 +35,17 @@
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-core_2.11</artifactId>
+            <artifactId>spark-core_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-sql_2.11</artifactId>
+            <artifactId>spark-sql_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>pl.edu.icm.spark-utils</groupId>
-            <artifactId>spark-utils_2.11</artifactId>
+            <artifactId>spark-utils_2.12</artifactId>
         </dependency>
 
         <dependency>
diff --git a/iis-wf/iis-wf-citationmatching-direct/pom.xml b/iis-wf/iis-wf-citationmatching-direct/pom.xml
index c24e9043f..85e856684 100644
--- a/iis-wf/iis-wf-citationmatching-direct/pom.xml
+++ b/iis-wf/iis-wf-citationmatching-direct/pom.xml
@@ -36,17 +36,17 @@
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-core_2.11</artifactId>
+            <artifactId>spark-core_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-sql_2.11</artifactId>
+            <artifactId>spark-sql_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>pl.edu.icm.spark-utils</groupId>
-            <artifactId>spark-utils_2.11</artifactId>
+            <artifactId>spark-utils_2.12</artifactId>
         </dependency>
     </dependencies>
 
diff --git a/iis-wf/iis-wf-citationmatching/pom.xml b/iis-wf/iis-wf-citationmatching/pom.xml
index fdeebae2d..3cbe12031 100644
--- a/iis-wf/iis-wf-citationmatching/pom.xml
+++ b/iis-wf/iis-wf-citationmatching/pom.xml
@@ -18,6 +18,28 @@
             <groupId>eu.dnetlib.iis</groupId>
             <artifactId>iis-common</artifactId>
             <version>${project.version}</version>
+            <exclusions>
+                <exclusion>
+                    <!-- conflicting scala binary versions -->
+                    <groupId>org.scala-lang</groupId>
+                    <artifactId>scala-library</artifactId>
+                </exclusion>
+                <exclusion>
+                    <!-- conflicting scala binary versions -->
+                    <groupId>org.apache.spark</groupId>
+                    <artifactId>spark-core_2.12</artifactId>
+                </exclusion>
+                <exclusion>
+                    <!-- conflicting scala binary versions -->
+                    <groupId>org.apache.spark</groupId>
+                    <artifactId>spark-sql_2.12</artifactId>
+                </exclusion>
+                <exclusion>
+                    <!-- conflicting scala binary versions -->
+                    <groupId>pl.edu.icm.spark-utils</groupId>
+                    <artifactId>spark-utils_2.12</artifactId>
+                </exclusion>
+            </exclusions>
         </dependency>
 
         <dependency>
@@ -38,6 +60,28 @@
             <version>${project.version}</version>
             <type>test-jar</type>
             <scope>test</scope>
+            <exclusions>
+                <exclusion>
+                    <!-- conflicting scala binary versions -->
+                    <groupId>org.scala-lang</groupId>
+                    <artifactId>scala-library</artifactId>
+                </exclusion>
+                <exclusion>
+                    <!-- conflicting scala binary versions -->
+                    <groupId>org.apache.spark</groupId>
+                    <artifactId>spark-core_2.12</artifactId>
+                </exclusion>
+                <exclusion>
+                    <!-- conflicting scala binary versions -->
+                    <groupId>org.apache.spark</groupId>
+                    <artifactId>spark-sql_2.12</artifactId>
+                </exclusion>
+                <exclusion>
+                    <!-- conflicting scala binary versions -->
+                    <groupId>pl.edu.icm.spark-utils</groupId>
+                    <artifactId>spark-utils_2.12</artifactId>
+                </exclusion>
+            </exclusions>
         </dependency>
 
         <dependency>
diff --git a/iis-wf/iis-wf-documentsclassification/pom.xml b/iis-wf/iis-wf-documentsclassification/pom.xml
index b084b27a5..0a499a20c 100644
--- a/iis-wf/iis-wf-documentsclassification/pom.xml
+++ b/iis-wf/iis-wf-documentsclassification/pom.xml
@@ -53,17 +53,17 @@
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-core_2.11</artifactId>
+            <artifactId>spark-core_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-sql_2.11</artifactId>
+            <artifactId>spark-sql_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>pl.edu.icm.spark-utils</groupId>
-            <artifactId>spark-utils_2.11</artifactId>
+            <artifactId>spark-utils_2.12</artifactId>
         </dependency>
 
         <dependency>
diff --git a/iis-wf/iis-wf-documentssimilarity/pom.xml b/iis-wf/iis-wf-documentssimilarity/pom.xml
index 7f2280e03..f91b992c8 100644
--- a/iis-wf/iis-wf-documentssimilarity/pom.xml
+++ b/iis-wf/iis-wf-documentssimilarity/pom.xml
@@ -53,13 +53,13 @@
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-core_2.11</artifactId>
+            <artifactId>spark-core_2.12</artifactId>
             <scope>test</scope>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-sql_2.11</artifactId>
+            <artifactId>spark-sql_2.12</artifactId>
             <scope>test</scope>
         </dependency>
 
diff --git a/iis-wf/iis-wf-export-actionmanager/pom.xml b/iis-wf/iis-wf-export-actionmanager/pom.xml
index 9025e5ffc..e4e44a175 100644
--- a/iis-wf/iis-wf-export-actionmanager/pom.xml
+++ b/iis-wf/iis-wf-export-actionmanager/pom.xml
@@ -76,22 +76,22 @@
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-core_2.11</artifactId>
+            <artifactId>spark-core_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-sql_2.11</artifactId>
+            <artifactId>spark-sql_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-avro_2.11</artifactId>
+            <artifactId>spark-avro_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>pl.edu.icm.spark-utils</groupId>
-            <artifactId>spark-utils_2.11</artifactId>
+            <artifactId>spark-utils_2.12</artifactId>
         </dependency>
     </dependencies>
 
diff --git a/iis-wf/iis-wf-import/pom.xml b/iis-wf/iis-wf-import/pom.xml
index f6c86dac2..35f8f4b43 100644
--- a/iis-wf/iis-wf-import/pom.xml
+++ b/iis-wf/iis-wf-import/pom.xml
@@ -115,27 +115,27 @@
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-core_2.11</artifactId>
+            <artifactId>spark-core_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-sql_2.11</artifactId>
+            <artifactId>spark-sql_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>pl.edu.icm.spark-utils</groupId>
-            <artifactId>spark-utils_2.11</artifactId>
+            <artifactId>spark-utils_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-avro_2.11</artifactId>
+            <artifactId>spark-avro_2.12</artifactId>
         </dependency>
         
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-hive_2.11</artifactId>
+            <artifactId>spark-hive_2.12</artifactId>
             <exclusions>
                 <exclusion>
                     <!-- unavailable dependency in cloudera repo -->
diff --git a/iis-wf/iis-wf-referenceextraction/pom.xml b/iis-wf/iis-wf-referenceextraction/pom.xml
index a58252eae..3cb57c26f 100644
--- a/iis-wf/iis-wf-referenceextraction/pom.xml
+++ b/iis-wf/iis-wf-referenceextraction/pom.xml
@@ -66,22 +66,22 @@
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-core_2.11</artifactId>
+            <artifactId>spark-core_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-sql_2.11</artifactId>
+            <artifactId>spark-sql_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-avro_2.11</artifactId>
+            <artifactId>spark-avro_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>pl.edu.icm.spark-utils</groupId>
-            <artifactId>spark-utils_2.11</artifactId>
+            <artifactId>spark-utils_2.12</artifactId>
         </dependency>
         
         <dependency>
diff --git a/iis-wf/iis-wf-transformers/pom.xml b/iis-wf/iis-wf-transformers/pom.xml
index a6dbef295..8a332aeff 100644
--- a/iis-wf/iis-wf-transformers/pom.xml
+++ b/iis-wf/iis-wf-transformers/pom.xml
@@ -51,17 +51,17 @@
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-core_2.11</artifactId>
+            <artifactId>spark-core_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>org.apache.spark</groupId>
-            <artifactId>spark-sql_2.11</artifactId>
+            <artifactId>spark-sql_2.12</artifactId>
         </dependency>
 
         <dependency>
             <groupId>pl.edu.icm.spark-utils</groupId>
-            <artifactId>spark-utils_2.11</artifactId>
+            <artifactId>spark-utils_2.12</artifactId>
         </dependency>
     </dependencies>
 
diff --git a/pom.xml b/pom.xml
index 91f5813d5..5032949b5 100644
--- a/pom.xml
+++ b/pom.xml
@@ -321,36 +321,36 @@
 
             <dependency>
                 <groupId>org.apache.spark</groupId>
-                <artifactId>spark-core_2.11</artifactId>
+                <artifactId>spark-core_2.12</artifactId>
                 <version>${iis.spark.version}</version>
                 <scope>provided</scope>
             </dependency>
 
             <dependency>
                 <groupId>org.apache.spark</groupId>
-                <artifactId>spark-sql_2.11</artifactId>
+                <artifactId>spark-sql_2.12</artifactId>
                 <version>${iis.spark.version}</version>
                 <scope>provided</scope>
             </dependency>
 
             <dependency>
                 <groupId>org.apache.spark</groupId>
-                <artifactId>spark-avro_2.11</artifactId>
+                <artifactId>spark-avro_2.12</artifactId>
                 <version>${iis.spark.version}</version>
                 <scope>provided</scope>
             </dependency>
             
             <dependency>
                 <groupId>org.apache.spark</groupId>
-                <artifactId>spark-hive_2.11</artifactId>
+                <artifactId>spark-hive_2.12</artifactId>
                 <version>${iis.spark.version}</version>
                 <scope>provided</scope>
             </dependency>
 
             <dependency>
                 <groupId>pl.edu.icm.spark-utils</groupId>
-                <artifactId>spark-utils_2.11</artifactId>
-                <version>1.0.1</version>
+                <artifactId>spark-utils_2.12</artifactId>
+                <version>1.0.2</version>
                 <scope>provided</scope>
             </dependency>
 
@@ -1017,7 +1017,7 @@
         <iis.pig.version>0.12.0-${iis.cdh.version}</iis.pig.version>
         <iis.avro.version>1.7.6-${iis.cdh.version}</iis.avro.version>
         <iis.hadoop.version>2.6.0-${iis.cdh.version}</iis.hadoop.version>
-        <iis.spark.version>2.4.0.cloudera2</iis.spark.version>
+        <iis.spark.version>3.4.1</iis.spark.version>
         <iis.coansys.version>1.10</iis.coansys.version>
 
         <junit.version>5.8.2</junit.version>