#fixed code
                                @Override
    public Object configure(Object c) throws Exception {
        final ExtensionList list = Jenkins.getInstance().getExtensionList(target);
        if (list.size() != 1) {
            throw new IllegalStateException();
        }
        final Object o = list.get(0);

        if (c instanceof Map) {
            Map config = (Map) c;
            final Set<Attribute> attributes = describe();
            for (Attribute attribute : attributes) {
                final String name = attribute.getName();
                if (config.containsKey(name)) {
                    final Class k = attribute.getType();
                    final Configurator configurator = Configurator.lookup(k);
                    if (configurator == null) throw new IllegalStateException("No configurator implementation to manage "+ k);
                    final Object value = configurator.configure(config.get(name));
                    attribute.setValue(o, value);
                }
            }
        }

        return o;
    }
#vulnerable code 
                                @Override
    public Object configure(Object c) throws Exception {
        final ExtensionList list = Jenkins.getInstance().getExtensionList(target);
        if (list.size() != 1) {
            throw new IllegalStateException();
        }
        final Object o = list.get(0);

        if (c instanceof Map) {
            Map config = (Map) c;
            final Set<Attribute> attributes = describe();
            for (Attribute attribute : attributes) {
                final String name = attribute.getName();
                if (config.containsKey(name)) {
                    final Object value = Configurator.lookup(attribute.getType()).configure(config.get(name));
                    attribute.setValue(o, value);
                }
            }
        }

        return o;
    } 
                            #location 15 
                            #vulnerability type NULL_DEREFERENCE