  cff_get_glyph_data( TT_Face    face,
                      FT_UInt    glyph_index,
                      FT_Byte**  pointer,
                      FT_ULong*  length )
  {
#ifdef FT_CONFIG_OPTION_INCREMENTAL
    /* For incremental fonts get the character data using the */
    /* callback function.                                     */
    if ( face->root.internal->incremental_interface )
    {
      FT_Data   data;
      FT_Error  error =
                  face->root.internal->incremental_interface->funcs->get_glyph_data(
                    face->root.internal->incremental_interface->object,
                    glyph_index, &data );


      *pointer = (FT_Byte*)data.pointer;
      *length = data.length;

      return error;
    }
    else
#endif /* FT_CONFIG_OPTION_INCREMENTAL */

    {
      CFF_Font  cff  = (CFF_Font)(face->extra.data);


      return cff_index_access_element( &cff->charstrings_index, glyph_index,
                                       pointer, length );
    }
  }

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.