output: #fixed code
                                @Override
    public void run() {
      final Set<String> artifacts = new HashSet<>();
      installNodeModules(artifacts);
  
      final File base = new File(cwd, "node_modules");
      final File libs = new File(base, ".lib");
  
      if (force || libs.exists()) {
        final double version = Double.parseDouble(System.getProperty("java.specification.version"));
        final boolean isGraalVM =
          System.getProperty("java.vm.name", "").toLowerCase().contains("graalvm") ||
          // from graal 20.0.0 the vm name doesn't contain graalvm in the name
          // but it is now part of the vendor version
          System.getProperty("java.vendor.version", "").toLowerCase().contains("graalvm");
  
        if (!isGraalVM) {
  
          // not on graal, install graaljs and dependencies
          warn("Installing GraalJS...");
          // graaljs + dependencies
          installGraalJS(artifacts);
  
          if (version >= 11) {
            // verify if the current JDK contains the jdk.internal.vm.ci module
            try {
              String modules = exec(javaHomePrefix() + "java", "--list-modules");
              if (modules.contains("jdk.internal.vm.ci")) {
                warn("Installing JVMCI Compiler...");
                // jvmci compiler + dependencies
                installGraalJMVCICompiler();
              }
            } catch (IOException | InterruptedException e) {
              err(e.getMessage());
            }
          } else {
            warn("Current JDK only supports GraalJS in Interpreted mode!");
          }
        }
      }
  
      // always create a launcher even if no dependencies are needed
      createLauncher(artifacts);
      // always install the es4x type definitions
      installTypeDefinitions();
    }
input: #vulnerable code 
                                @Override
    public void run() {
      final Set<String> artifacts = new HashSet<>();
      installNodeModules(artifacts);
  
      final File base = new File(cwd, "node_modules");
      final File libs = new File(base, ".lib");
  
      if (force || libs.exists()) {
        final double version = Double.parseDouble(System.getProperty("java.specification.version"));
        final String vm = System.getProperty("java.vm.name");
        // from graal 20.0.0 the vm name doesn't contain graalvm in the name
        // but it is now part of the vendor version
        final String vendor = System.getProperty("java.vendor.version");
        if (!vm.toLowerCase().contains("graalvm") && vendor != null && !vendor.toLowerCase().contains("graalvm")) {
  
          // not on graal, install graaljs and dependencies
          warn("Installing GraalJS...");
          // graaljs + dependencies
          installGraalJS(artifacts);
  
          if (version >= 11) {
            // verify if the current JDK contains the jdk.internal.vm.ci module
            try {
              String modules = exec(javaHomePrefix() + "java", "--list-modules");
              if (modules.contains("jdk.internal.vm.ci")) {
                warn("Installing JVMCI Compiler...");
                // jvmci compiler + dependencies
                installGraalJMVCICompiler();
              }
            } catch (IOException | InterruptedException e) {
              err(e.getMessage());
            }
          } else {
            warn("Current JDK only supports GraalJS in Interpreted mode!");
          }
        }
      }
  
      // always create a launcher even if no dependencies are needed
      createLauncher(artifacts);
      // always install the es4x type definitions
      installTypeDefinitions();
    } 
                              #location 15 
                              #vulnerability type NULL_DEREFERENCE