#vulnerable code 
                                private void useLatestSnapshots( ModifiedPomXMLEventReader pom, Collection dependencies )
        throws XMLStreamException, MojoExecutionException, ArtifactMetadataRetrievalException
    {
        int segment = determineUnchangedSegment(allowMajorUpdates, allowMinorUpdates,
                allowIncrementalUpdates);

        Iterator i = dependencies.iterator();

        while ( i.hasNext() )
        {
            Dependency dep = (Dependency) i.next();

            if ( isExcludeReactor() && isProducedByReactor( dep ) )
            {
                getLog().info( "Ignoring reactor dependency: " + toString( dep ) );
                continue;
            }

            String version = dep.getVersion();
            Matcher versionMatcher = matchSnapshotRegex.matcher( version );
            if ( !versionMatcher.matches() )
            {
                getLog().debug( "Looking for latest snapshot of " + toString( dep ) );
                Artifact artifact = this.toArtifact( dep );
                if ( !isIncluded( artifact ) )
                {
                    continue;
                }

                ArtifactVersions versions = getHelper().lookupArtifactVersions( artifact, false );
                final VersionComparator versionComparator = versions.getVersionComparator();
                final DefaultArtifactVersion lowerBound = new DefaultArtifactVersion( version );
                if ( segment + 1 > versionComparator.getSegmentCount( lowerBound ) )
                {
                    getLog().info( "Ignoring " + toString( dep ) + " as the version number is too short" );
                    continue;
                }
                ArtifactVersion upperBound = segment >= 0 ? versionComparator.incrementSegment( lowerBound, segment ) : null;
                getLog().info("Upper bound: " + upperBound.toString());
                ArtifactVersion[] newer = versions.getVersions( lowerBound, upperBound, true, false, false );
                getLog().debug( "Candidate versions " + Arrays.asList(newer));
                String latestVersion = null;
                for ( int j = 0; j < newer.length; j++ )
                {
                    String newVersion = newer[j].toString();
                    if ( matchSnapshotRegex.matcher( newVersion ).matches() )
                    {
                        latestVersion = newVersion;
                    }
                }
                if ( latestVersion != null )
                {
                    if ( PomHelper.setDependencyVersion( pom, dep.getGroupId(), dep.getArtifactId(), version,
                                                         latestVersion ) )
                    {
                        getLog().info( "Updated " + toString( dep ) + " to version " + latestVersion );
                    }
                }
            }
        }
    } 
                            #location 39 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                private void useLatestSnapshots( ModifiedPomXMLEventReader pom, Collection dependencies )
        throws XMLStreamException, MojoExecutionException, ArtifactMetadataRetrievalException
    {
        int segment = determineUnchangedSegment(allowMajorUpdates, allowMinorUpdates,
                allowIncrementalUpdates);

        Iterator i = dependencies.iterator();

        while ( i.hasNext() )
        {
            Dependency dep = (Dependency) i.next();

            if ( isExcludeReactor() && isProducedByReactor( dep ) )
            {
                getLog().info( "Ignoring reactor dependency: " + toString( dep ) );
                continue;
            }

            String version = dep.getVersion();
            Matcher versionMatcher = matchSnapshotRegex.matcher( version );
            if ( !versionMatcher.matches() )
            {
                getLog().debug( "Looking for latest snapshot of " + toString( dep ) );
                Artifact artifact = this.toArtifact( dep );
                if ( !isIncluded( artifact ) )
                {
                    continue;
                }

                ArtifactVersions versions = getHelper().lookupArtifactVersions( artifact, false );
                final VersionComparator versionComparator = versions.getVersionComparator();
                final DefaultArtifactVersion lowerBound = new DefaultArtifactVersion( version );
                if ( segment + 1 > versionComparator.getSegmentCount( lowerBound ) )
                {
                    getLog().info( "Ignoring " + toString( dep ) + " as the version number is too short" );
                    continue;
                }
                ArtifactVersion upperBound = segment >= 0 ? versionComparator.incrementSegment( lowerBound, segment ) : null;
                getLog().info("Upper bound: " + ( upperBound == null ? "none" : upperBound.toString() ) );
                ArtifactVersion[] newer = versions.getVersions( lowerBound, upperBound, true, false, false );
                getLog().debug( "Candidate versions " + Arrays.asList(newer));
                String latestVersion = null;
                for ( int j = 0; j < newer.length; j++ )
                {
                    String newVersion = newer[j].toString();
                    if ( matchSnapshotRegex.matcher( newVersion ).matches() )
                    {
                        latestVersion = newVersion;
                    }
                }
                if ( latestVersion != null )
                {
                    if ( PomHelper.setDependencyVersion( pom, dep.getGroupId(), dep.getArtifactId(), version,
                                                         latestVersion ) )
                    {
                        getLog().info( "Updated " + toString( dep ) + " to version " + latestVersion );
                    }
                }
            }
        }
    }