static Image *ReadFITSImage(const ImageInfo *image_info,
  ExceptionInfo *exception)
{
  typedef struct _FITSInfo
  {
    MagickBooleanType
      extend,
      simple;

    int
      bits_per_pixel,
      columns,
      rows,
      number_axes,
      number_planes;

    double
      min_data,
      max_data,
      zero,
      scale;

    EndianType
      endian;
  } FITSInfo;

  char
    *comment,
    keyword[9],
    property[MaxTextExtent],
    value[73];

  double
    pixel,
    scale;

  FITSInfo
    fits_info;

  Image
    *image;

  int
    c;

  MagickBooleanType
    status;

  MagickSizeType
    number_pixels;

  register ssize_t
    i,
    x;

  register PixelPacket
    *q;

  ssize_t
    count,
    scene,
    y;

  /*
    Open image file.
  */
  assert(image_info != (const ImageInfo *) NULL);
  assert(image_info->signature == MagickSignature);
  if (image_info->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
      image_info->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  image=AcquireImage(image_info);
  status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
  if (status == MagickFalse)
    {
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  /*
    Initialize image header.
  */
  (void) ResetMagickMemory(&fits_info,0,sizeof(fits_info));
  fits_info.extend=MagickFalse;
  fits_info.simple=MagickFalse;
  fits_info.bits_per_pixel=8;
  fits_info.columns=1;
  fits_info.rows=1;
  fits_info.rows=1;
  fits_info.number_planes=1;
  fits_info.min_data=0.0;
  fits_info.max_data=0.0;
  fits_info.zero=0.0;
  fits_info.scale=1.0;
  fits_info.endian=MSBEndian;
  /*
    Decode image header.
  */
  for (comment=(char *) NULL; EOFBlob(image) == MagickFalse; )
  {
    for ( ; EOFBlob(image) == MagickFalse; )
    {
      register char
        *p;

      count=ReadBlob(image,8,(unsigned char *) keyword);
      if (count != 8)
        break;
      for (i=0; i < 8; i++)
      {
        if (isspace((int) ((unsigned char) keyword[i])) != 0)
          break;
        keyword[i]=tolower((int) ((unsigned char) keyword[i]));
      }
      keyword[i]='\0';
      count=ReadBlob(image,72,(unsigned char *) value);
      value[72]='\0';
      if (count != 72)
        break;
      p=value;
      if (*p == '=')
        {
          p+=2;
          while (isspace((int) ((unsigned char) *p)) != 0)
            p++;
        }
      if (LocaleCompare(keyword,"end") == 0)
        break;
      if (LocaleCompare(keyword,"extend") == 0)
        fits_info.extend=(*p == 'T') || (*p == 't') ? MagickTrue : MagickFalse;
      if (LocaleCompare(keyword,"simple") == 0)
        fits_info.simple=(*p == 'T') || (*p == 't') ? MagickTrue : MagickFalse;
      if (LocaleCompare(keyword,"bitpix") == 0)
        fits_info.bits_per_pixel=StringToLong(p);
      if (LocaleCompare(keyword,"naxis") == 0)
        fits_info.number_axes=StringToLong(p);
      if (LocaleCompare(keyword,"naxis1") == 0)
        fits_info.columns=StringToLong(p);
      if (LocaleCompare(keyword,"naxis2") == 0)
        fits_info.rows=StringToLong(p);
      if (LocaleCompare(keyword,"naxis3") == 0)
        fits_info.number_planes=StringToLong(p);
      if (LocaleCompare(keyword,"datamax") == 0)
        fits_info.max_data=StringToDouble(p,(char **) NULL);
      if (LocaleCompare(keyword,"datamin") == 0)
        fits_info.min_data=StringToDouble(p,(char **) NULL);
      if (LocaleCompare(keyword,"bzero") == 0)
        fits_info.zero=StringToDouble(p,(char **) NULL);
      if (LocaleCompare(keyword,"bscale") == 0)
        fits_info.scale=StringToDouble(p,(char **) NULL);
      if (LocaleCompare(keyword,"comment") == 0)
        {
          if (comment == (char *) NULL)
            comment=ConstantString(p);
          else
            (void) ConcatenateString(&comment,p);
        }
      if (LocaleCompare(keyword,"xendian") == 0)
        {
          if (LocaleNCompare(p,"big",3) == 0)
            fits_info.endian=MSBEndian;
          else
            fits_info.endian=LSBEndian;
        }
      (void) FormatLocaleString(property,MaxTextExtent,"fits:%s",keyword);
      (void) SetImageProperty(image,property,p);
    }
    c=0;
    while (((TellBlob(image) % FITSBlocksize) != 0) && (c != EOF))
      c=ReadBlobByte(image);
    if (fits_info.extend == MagickFalse)
      break;
    number_pixels=(MagickSizeType) fits_info.columns*fits_info.rows;
    if ((fits_info.simple != MagickFalse) && (fits_info.number_axes >= 1) &&
        (fits_info.number_axes <= 4) && (number_pixels != 0))
      break;
  }
  /*
    Verify that required image information is defined.
  */
  if (comment != (char *) NULL)
    {
      (void) SetImageProperty(image,"comment",comment);
      comment=DestroyString(comment);
    }
  if (EOFBlob(image) != MagickFalse)
    ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
      image->filename);
  number_pixels=(MagickSizeType) fits_info.columns*fits_info.rows;
  if ((fits_info.simple == MagickFalse) || (fits_info.number_axes < 1) ||
      (fits_info.number_axes > 4) || (number_pixels == 0))
    ThrowReaderException(CorruptImageError,"ImageTypeNotSupported");
  for (scene=0; scene < (ssize_t) fits_info.number_planes; scene++)
  {
    image->columns=(size_t) fits_info.columns;
    image->rows=(size_t) fits_info.rows;
    image->depth=(size_t) (fits_info.bits_per_pixel < 0 ? -1 : 1)*
      fits_info.bits_per_pixel;
    image->endian=fits_info.endian;
    image->scene=(size_t) scene;
     if ((image_info->ping != MagickFalse) && (image_info->number_scenes != 0))
       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
         break;
    status=SetImageExtent(image,image->columns,image->rows);
    if (status == MagickFalse)
      {
        InheritException(exception,&image->exception);
        return(DestroyImageList(image));
      }
     /*
       Initialize image structure.
     */
    (void) SetImageColorspace(image,GRAYColorspace);
    if ((fits_info.min_data == 0.0) && (fits_info.max_data == 0.0))
      {
        if (fits_info.zero == 0.0)
          (void) GetFITSPixelExtrema(image,fits_info.bits_per_pixel,
            &fits_info.min_data,&fits_info.max_data);
        else
          fits_info.max_data=GetFITSPixelRange((size_t)
            fits_info.bits_per_pixel);
      }
    else
      fits_info.max_data=GetFITSPixelRange((size_t) fits_info.bits_per_pixel);
    /*
      Convert FITS pixels to pixel packets.
    */
    scale=QuantumRange/(fits_info.max_data-fits_info.min_data);
    for (y=(ssize_t) image->rows-1; y >= 0; y--)
    {
      q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
      if (q == (PixelPacket *) NULL)
        break;
      for (x=0; x < (ssize_t) image->columns; x++)
      {
        pixel=GetFITSPixel(image,fits_info.bits_per_pixel);
        if ((image->depth == 16) || (image->depth == 32) ||
            (image->depth == 64))
          SetFITSUnsignedPixels(1,image->depth,image->endian,(unsigned char *)
            &pixel);
        SetPixelRed(q,ClampToQuantum(scale*(fits_info.scale*(pixel-
          fits_info.min_data)+fits_info.zero)));
        SetPixelGreen(q,GetPixelRed(q));
        SetPixelBlue(q,GetPixelRed(q));
        q++;
      }
      if (SyncAuthenticPixels(image,exception) == MagickFalse)
        break;
      if (image->previous == (Image *) NULL)
        {
          status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
                image->rows);
          if (status == MagickFalse)
            break;
        }
    }
    if (EOFBlob(image) != MagickFalse)
      {
        ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
          image->filename);
        break;
      }
    /*
      Proceed to next image.
    */
    if (image_info->number_scenes != 0)
      if (image->scene >= (image_info->scene+image_info->number_scenes-1))
        break;
    if (scene < (ssize_t) (fits_info.number_planes-1))
      {
        /*
          Allocate next image structure.
        */
        AcquireNextImage(image_info,image);
        if (GetNextImageInList(image) == (Image *) NULL)
          {
            image=DestroyImageList(image);
            return((Image *) NULL);
          }
        image=SyncNextImageInList(image);
        status=SetImageProgress(image,LoadImagesTag,TellBlob(image),
          GetBlobSize(image));
        if (status == MagickFalse)
          break;
      }
  }
  (void) CloseBlob(image);
  return(GetFirstImageInList(image));
}

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.