static const char *parse_string( cJSON *item, const char *str )
 {
	const char *ptr = str + 1;
	char *ptr2;
	char *out;
	int len = 0;
	unsigned uc, uc2;
	if ( *str != '\"' ) {
		/* Not a string! */
		ep = str;
		return 0;
	}
 	
	/* Skip escaped quotes. */
	while ( *ptr != '\"' && *ptr && ++len )
		if ( *ptr++ == '\\' )
			ptr++;
 	
	if ( ! ( out = (char*) cJSON_malloc( len + 1 ) ) )
		return 0;
 	
	ptr = str + 1;
	ptr2 = out;
	while ( *ptr != '\"' && *ptr ) {
		if ( *ptr != '\\' )
			*ptr2++ = *ptr++;
		else {
 			ptr++;
			switch ( *ptr ) {
				case 'b': *ptr2++ ='\b'; break;
				case 'f': *ptr2++ ='\f'; break;
				case 'n': *ptr2++ ='\n'; break;
				case 'r': *ptr2++ ='\r'; break;
				case 't': *ptr2++ ='\t'; break;
				case 'u':
					/* Transcode utf16 to utf8. */
					/* Get the unicode char. */
					sscanf( ptr + 1,"%4x", &uc );
					ptr += 4;
					/* Check for invalid. */
					if ( ( uc >= 0xDC00 && uc <= 0xDFFF ) || uc == 0 )
						break;
					/* UTF16 surrogate pairs. */
					if ( uc >= 0xD800 && uc <= 0xDBFF ) {
						if ( ptr[1] != '\\' || ptr[2] != 'u' )
							/* Missing second-half of surrogate. */
							break;
						sscanf( ptr + 3, "%4x", &uc2 );
						ptr += 6;
						if ( uc2 < 0xDC00 || uc2 > 0xDFFF )
							/* Invalid second-half of surrogate. */
							break;
						uc = 0x10000 | ( ( uc & 0x3FF ) << 10 ) | ( uc2 & 0x3FF );
 					}
 
					len = 4;
					if ( uc < 0x80 )
						len = 1;
					else if ( uc < 0x800 )
						len = 2;
					else if ( uc < 0x10000 )
						len = 3;
					ptr2 += len;
 					
					switch ( len ) {
						case 4: *--ptr2 = ( ( uc | 0x80) & 0xBF ); uc >>= 6;
						case 3: *--ptr2 = ( ( uc | 0x80) & 0xBF ); uc >>= 6;
						case 2: *--ptr2 = ( ( uc | 0x80) & 0xBF ); uc >>= 6;
						case 1: *--ptr2 = ( uc | firstByteMark[len] );
 					}
					ptr2 += len;
 					break;
				default:  *ptr2++ = *ptr; break;
 			}
			++ptr;
 		}
 	}
	*ptr2 = 0;
	if ( *ptr == '\"' )
		++ptr;
	item->valuestring = out;
	item->type = cJSON_String;
 	return ptr;
 }

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.