MagickExport MagickBooleanType ContrastImage(Image *image,
  const MagickBooleanType sharpen,ExceptionInfo *exception)
{
#define ContrastImageTag  "Contrast/Image"

  CacheView
    *image_view;

  int
    sign;

  MagickBooleanType
    status;

  MagickOffsetType
    progress;

  register ssize_t
    i;

  ssize_t
    y;

  assert(image != (Image *) NULL);
  assert(image->signature == MagickCoreSignature);
#if defined(MAGICKCORE_OPENCL_SUPPORT)
  if (AccelerateContrastImage(image,sharpen,exception) != MagickFalse)
    return(MagickTrue);
#endif
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  sign=sharpen != MagickFalse ? 1 : -1;
  if (image->storage_class == PseudoClass)
    {
      /*
        Contrast enhance colormap.
      */
      for (i=0; i < (ssize_t) image->colors; i++)
      {
        double
          blue,
          green,
          red;

        red=(double) image->colormap[i].red;
        green=(double) image->colormap[i].green;
        blue=(double) image->colormap[i].blue;
        Contrast(sign,&red,&green,&blue);
        image->colormap[i].red=(MagickRealType) red;
        image->colormap[i].green=(MagickRealType) green;
        image->colormap[i].blue=(MagickRealType) blue;
      }
    }
  /*
    Contrast enhance image.
  */
  status=MagickTrue;
  progress=0;
  image_view=AcquireAuthenticCacheView(image,exception);
#if defined(MAGICKCORE_OPENMP_SUPPORT)
  #pragma omp parallel for schedule(static) shared(progress,status) \
    magick_number_threads(image,image,image->rows,1)
#endif
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    double
      blue,
      green,
      red;

    register Quantum
      *magick_restrict q;

    register ssize_t
      x;

    if (status == MagickFalse)
      continue;
    q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
    if (q == (Quantum *) NULL)
      {
        status=MagickFalse;
        continue;
      }
    for (x=0; x < (ssize_t) image->columns; x++)
    {
      red=(double) GetPixelRed(image,q);
      green=(double) GetPixelGreen(image,q);
      blue=(double) GetPixelBlue(image,q);
      Contrast(sign,&red,&green,&blue);
      SetPixelRed(image,ClampToQuantum(red),q);
      SetPixelGreen(image,ClampToQuantum(green),q);
      SetPixelBlue(image,ClampToQuantum(blue),q);
      q+=GetPixelChannels(image);
    }
    if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
      status=MagickFalse;
    if (image->progress_monitor != (MagickProgressMonitor) NULL)
      {
        MagickBooleanType
          proceed;

#if defined(MAGICKCORE_OPENMP_SUPPORT)
        #pragma omp atomic
#endif
        progress++;
        proceed=SetImageProgress(image,ContrastImageTag,progress,image->rows);
        if (proceed == MagickFalse)
          status=MagickFalse;
      }
  }
  image_view=DestroyCacheView(image_view);
  return(status);
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.