I am gettting below error in logs even when i have added an entry in /etc/sysconfig/tomcat6 in JAVAOPTS="org.apache.maven.artifact.versioning.ComparableVersion$ListItem "

so the workaround does not work in this case.

Please check this issue

WARNING: org.apache.maven.artifact.versioning.ComparableVersion$ListItem in file:/var/hudson/master/plugins/maven-plugin/WEB-INF/li
b/maven-artifact-3.1.0.jar might be dangerous, so rejecting; see https://jenkins.io/redirect/class-filter/
java.lang.SecurityException: Class rejected by the class filter: org.apache.maven.artifact.versioning.ComparableVersion$ListItem
at jenkins.security.ClassFilterImpl.notifyRejected(ClassFilterImpl.java:335)
at jenkins.security.ClassFilterImpl.lambda$isBlacklisted$1(ClassFilterImpl.java:185)
at java.util.Map.computeIfAbsent(Map.java:957)
at java.util.Collections$SynchronizedMap.computeIfAbsent(Collections.java:2672)
at jenkins.security.ClassFilterImpl.isBlacklisted(ClassFilterImpl.java:140)
at hudson.remoting.ClassFilter$1.isBlacklisted(ClassFilter.java:121)
at hudson.util.XStream2$BlacklistedTypesConverter.canConvert(XStream2.java:567)
at com.thoughtworks.xstream.core.DefaultConverterLookup.lookupConverterForType(DefaultConverterLookup.java:59)
at com.thoughtworks.xstream.XStream$1.lookupConverterForType(XStream.java:498)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:56)
at hudson.util.RobustReflectionConverter.unmarshalField(RobustReflectionConverter.java:393)
at hudson.util.RobustReflectionConverter.doUnmarshal(RobustReflectionConverter.java:331)
at hudson.util.RobustReflectionConverter.unmarshal(RobustReflectionConverter.java:270)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at hudson.util.RobustReflectionConverter.unmarshalField(RobustReflectionConverter.java:393)
at hudson.util.RobustReflectionConverter.doUnmarshal(RobustReflectionConverter.java:331)
at hudson.util.RobustReflectionConverter.unmarshal(RobustReflectionConverter.java:270)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at hudson.util.RobustReflectionConverter.unmarshalField(RobustReflectionConverter.java:393)
at hudson.util.RobustReflectionConverter.doUnmarshal(RobustReflectionConverter.java:331)
at hudson.util.RobustReflectionConverter.unmarshal(RobustReflectionConverter.java:270)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.readItem(AbstractCollectionConverter.java:71
)
at hudson.util.RobustCollectionConverter.populateCollection(RobustCollectionConverter.java:85)
at com.thoughtworks.xstream.converters.collections.CollectionConverter.unmarshal(CollectionConverter.java:80)
at hudson.util.RobustCollectionConverter.unmarshal(RobustCollectionConverter.java:76)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at hudson.util.RobustReflectionConverter.unmarshalField(RobustReflectionConverter.java:393)
at hudson.util.RobustReflectionConverter.doUnmarshal(RobustReflectionConverter.java:331)
at hudson.util.RobustReflectionConverter.unmarshal(RobustReflectionConverter.java:270)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:134)
at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:32)
at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1189)
at hudson.util.XStream2.unmarshal(XStream2.java:161)
at hudson.util.XStream2.unmarshal(XStream2.java:132)

at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1173)
at com.thoughtworks.xstream.XStream.fromXML(XStream.java:1053)
at hudson.XmlFile.read(XmlFile.java:147)
at hudson.model.Items.load(Items.java:371)
at hudson.model.ItemGroupMixIn.loadChildren(ItemGroupMixIn.java:118)
at hudson.maven.MavenModuleSet.onLoad(MavenModuleSet.java:812)
at hudson.model.Items.load(Items.java:372)
at jenkins.model.Jenkins$14.run(Jenkins.java:3125)
at org.jvnet.hudson.reactor.TaskGraphBuilder$TaskImpl.run(TaskGraphBuilder.java:169)
at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:296)
at jenkins.model.Jenkins$5.runTask(Jenkins.java:1066)
at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:214)
at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:117)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)