static MagickBooleanType WriteHRZImage(const ImageInfo *image_info,Image *image)
{
  Image
    *hrz_image;

  MagickBooleanType
    status;

  register const PixelPacket
    *p;

  register ssize_t
    x,
    y;

  register unsigned char
    *q;

  ssize_t
    count;

  unsigned char
    *pixels;

  /*
    Open output image file.
  */
  assert(image_info != (const ImageInfo *) NULL);
  assert(image_info->signature == MagickSignature);
  assert(image != (Image *) NULL);
  assert(image->signature == MagickSignature);
  if (image->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
  status=OpenBlob(image_info,image,WriteBinaryBlobMode,&image->exception);
  if (status == MagickFalse)
    return(status);
  hrz_image=ResizeImage(image,256,240,image->filter,image->blur,
    &image->exception);
  if (hrz_image == (Image *) NULL)
    return(MagickFalse);
  (void) TransformImageColorspace(hrz_image,sRGBColorspace);
  /*
    Allocate memory for pixels.
  */
  pixels=(unsigned char *) AcquireQuantumMemory((size_t) hrz_image->columns,
    3*sizeof(*pixels));
  if (pixels == (unsigned char *) NULL)
    {
      hrz_image=DestroyImage(hrz_image);
      ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
    }
  /*
    Convert MIFF to HRZ raster pixels.
  */
  for (y=0; y < (ssize_t) hrz_image->rows; y++)
  {
    p=GetVirtualPixels(hrz_image,0,y,hrz_image->columns,1,&image->exception);
    if (p == (PixelPacket *) NULL)
      break;
    q=pixels;
    for (x=0; x < (ssize_t) hrz_image->columns; x++)
    {
      *q++=ScaleQuantumToChar(GetPixelRed(p)/4);
      *q++=ScaleQuantumToChar(GetPixelGreen(p)/4);
      *q++=ScaleQuantumToChar(GetPixelBlue(p)/4);
      p++;
    }
    count=WriteBlob(image,(size_t) (q-pixels),pixels);
    if (count != (ssize_t) (q-pixels))
      break;
    status=SetImageProgress(image,SaveImageTag,y,hrz_image->rows);
    if (status == MagickFalse)
      break;
  }
  pixels=(unsigned char *) RelinquishMagickMemory(pixels);
  hrz_image=DestroyImage(hrz_image);
  (void) CloseBlob(image);
  return(MagickTrue);
}

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.