输入验证与表示问题是由元字符、交替编码和数字表示引起的。安全问题源于信任输入。这些问题包括：“Buffer Overflows”、“Cross-Site Scripting”攻击、“SQL Injection”等其他问题。
select() 查询，该查询可搜索与用户指定产品类别相匹配的清单。用户还可以指定对结果进行排序的列。假定在执行此代码片段之前已正确验证了应用程序并设置了 customerID 的值。
...
String customerID = getAuthenticatedCustomerID(customerName, customerCredentials);
...
AmazonSimpleDBClient sdbc = new AmazonSimpleDBClient(appAWSCredentials);
String query = "select * from invoices where productCategory = '"
+ productCategory + "' and customerID = '"
+ customerID + "' order by '"
+ sortColumn + "' asc";
SelectResult sdbResult = sdbc.select(new SelectRequest(query));
...
select * from invoices
where productCategory = 'Fax Machines'
and customerID = '12345678'
order by 'price' asc
productCategory 和 price 不包含单引号字符时，才会正确执行这一查询。但是，如果攻击者为 productCategory 提供了字符串“Fax Machines' or productCategory = \"”，并为 sortColumn 提供了字符串“\" order by 'price”，则查询将变为如下所示：
select * from invoices
where productCategory = 'Fax Machines' or productCategory = "'
and customerID = '12345678'
order by '" order by 'price' asc
select * from invoices
where productCategory = 'Fax Machines'
or productCategory = "' and customerID = '12345678' order by '"
order by 'price' asc
customerID 所要求的 Authentication，并查看与 'Fax Machines' 相匹配的所有客户清单记录。customerID 的值。
...
productCategory = this.getIntent().getExtras().getString("productCategory");
sortColumn = this.getIntent().getExtras().getString("sortColumn");
customerID = getAuthenticatedCustomerID(customerName, customerCredentials);
c = invoicesDB.query(Uri.parse(invoices), columns, "productCategory = '" + productCategory + "' and customerID = '" + customerID + "'", null, null, null, "'" + sortColumn + "'asc", null);
...
select * from invoices
where productCategory = 'Fax Machines'
and customerID = '12345678'
order by 'price' asc
productCategory 连在一起形成。因此只有在 productCategory 与 sortColumn 不包含单引号字符时，这一查询才能正确执行。如果攻击者为 productCategory 提供了字符串“Fax Machines' or productCategory = \"”，并为 sortColumn 提供了字符串“\" order by 'price”，则查询将变为如下所示：
select * from invoices
where productCategory = 'Fax Machines' or productCategory = "'
and customerID = '12345678'
order by '" order by 'price' asc
select * from invoices
where productCategory = 'Fax Machines'
or productCategory = "' and customerID = '12345678' order by '"
order by 'price' asc
customerID 所要求的 authentication，并查看与 'Fax Machines' 相匹配的所有客户清单记录。Content-Disposition 标头配置错误，攻击者可以控制 HTTP 响应的 Content-Type 和/或 Content-Disposition 标头，或者目标应用程序包含 Content-Type（默认不会在浏览器中呈现）。ContentNegotiationManager 动态生成不同的响应格式，则满足发动 RFD 攻击的必要条件。ContentNegotiationManager 配置为根据请求路径扩展决定响应格式，使用 Java Activation Framework (JAF) 查找与客户端请求格式更匹配的 Content-Type。同时，客户端也可以通过请求的 Accept 标头中发送的媒体类型来指定响应内容类型。示例 2：在以下示例中，应用程序配置为允许通过请求的
<bean id="contentNegotiationManager" class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean">
<property name="favorPathExtension" value="true" />
<property name="useJaf" value="true" />
</bean>
Accept 标头确定响应内容类型：
<bean id="contentNegotiationManager" class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean">
<property name="ignoreAcceptHeader" value="false" />
</bean>
ContentNegotiationManagerFactoryBean 属性默认值为：useJaf：truefavorPathExtension：trueignoreAcceptHeader：falseExample 1 中所示的配置允许攻击者创建一个恶意 URL，例如：ContentNegotiationManager 将使用 Java Activation Framework（如果在类路径中发现 activation.jar）尝试解析给定文件扩展名的媒体类型，并相应设置响应的 ContentType 标头。在此示例中，文件扩展名是“bat”，进而生成 application/x-msdownload 的 Content-Type 标头（尽管实际 Content-Type 可能因服务器 OS 和 JAF 配置而异）。因此，一旦受害者访问此恶意 URL，他/她的计算机将自动开始下载包含攻击者控制内容的“.bat”文件。如果随后执行此文件，受害者计算机将运行攻击者有效负载指定的任何命令。
...
host_name = request->get_form_field( 'host' ).
CALL FUNCTION 'FTP_CONNECT'
EXPORTING
USER = user
PASSWORD = password
HOST = host_name
RFC_DESTINATION = 'SAPFTP'
IMPORTING
HANDLE = mi_handle
EXCEPTIONS
NOT_CONNECTED = 1
OTHERS = 2.
...
int rPort = Int32.Parse(Request.Item("rPort"));
...
IPEndPoint endpoint = new IPEndPoint(address,rPort);
socket = new Socket(endpoint.AddressFamily,
SocketType.Stream, ProtocolType.Tcp);
socket.Connect(endpoint);
...
...
char* rPort = getenv("rPort");
...
serv_addr.sin_port = htons(atoi(rPort));
if (connect(sockfd,&serv_addr,sizeof(serv_addr)) < 0)
error("ERROR connecting");
...
...
ACCEPT QNAME.
EXEC CICS
READQ TD
QUEUE(QNAME)
INTO(DATA)
LENGTH(LDATA)
END-EXEC.
...
ServerSocket 对象，并使用读取自 HTTP 请求的端口号来建立一个套接字。
<cfobject action="create" type="java" class="java.net.ServerSocket" name="myObj">
<cfset srvr = myObj.init(#url.port#)>
<cfset socket = srvr.accept()>
Passing user input to objects imported from other languages can be very dangerous.
final server = await HttpServer.bind('localhost', 18081);
server.listen((request) async {
final remotePort = headers.value('port');
final serverSocket = await ServerSocket.bind(host, remotePort as int);
final httpServer = HttpServer.listenOn(serverSocket);
});
...
func someHandler(w http.ResponseWriter, r *http.Request){
r.parseForm()
deviceName := r.FormValue("device")
...
syscall.BindToDevice(fd, deviceName)
}
String remotePort = request.getParameter("remotePort");
...
ServerSocket srvr = new ServerSocket(remotePort);
Socket skt = srvr.accept();
...
WebView 中加载页面。
...
WebView webview = new WebView(this);
setContentView(webview);
String url = this.getIntent().getExtras().getString("url");
webview.loadUrl(url);
...
var socket = new WebSocket(document.URL.indexOf("url=")+20);
...
char* rHost = getenv("host");
...
CFReadStreamRef readStream;
CFWriteStreamRef writeStream;
CFStreamCreatePairWithSocketToHost(NULL, (CFStringRef)rHost, 80, &readStream, &writeStream);
...
<?php
$host=$_GET['host'];
$dbconn = pg_connect("host=$host port=1234 dbname=ticketdb");
...
$result = pg_prepare($dbconn, "my_query", 'SELECT * FROM pricelist WHERE name = $1');
$result = pg_execute($dbconn, "my_query", array("ticket"));
?>
...
filename := SUBSTR(OWA_UTIL.get_cgi_env('PATH_INFO'), 2);
WPG_DOCLOAD.download_file(filename);
...
host=request.GET['host']
dbconn = db.connect(host=host, port=1234, dbname=ticketdb)
c = dbconn.cursor()
...
result = c.execute('SELECT * FROM pricelist')
...
def controllerMethod = Action { request =>
val result = request.getQueryString("key").map { key =>
val user = db.getUser()
cache.set(key, user)
Ok("Cached Request")
}
Ok("Done")
}
...
func application(app: UIApplication, openURL url: NSURL, options: [String : AnyObject]) -> Bool {
var inputStream : NSInputStream?
var outputStream : NSOutputStream?
...
var readStream : Unmanaged<CFReadStream>?
var writeStream : Unmanaged<CFWriteStream>?
let rHost = getQueryStringParameter(url.absoluteString, "host")
CFStreamCreatePairWithSocketToHost(kCFAllocatorDefault, rHost, 80, &readStream, &writeStream);
...
}
func getQueryStringParameter(url: String?, param: String) -> String? {
if let url = url, urlComponents = NSURLComponents(string: url), queryItems = (urlComponents.queryItems as? [NSURLQueryItem]) {
return queryItems.filter({ (item) in item.name == param }).first?.value!
}
return nil
}
...
...
Begin MSWinsockLib.Winsock tcpServer
...
Dim Response As Response
Dim Request As Request
Dim Session As Session
Dim Application As Application
Dim Server As Server
Dim Port As Variant
Set Response = objContext("Response")
Set Request = objContext("Request")
Set Session = objContext("Session")
Set Application = objContext("Application")
Set Server = objContext("Server")
Set Port = Request.Form("port")
...
tcpServer.LocalPort = Port
tcpServer.Accept
...
@ControllerAdvice
public class JsonpAdvice extends AbstractJsonpResponseBodyAdvice {
public JsonpAdvice() {
super("callback");
}
}
GET /api/latest.json?callback=myCallbackFunction 等请求，控制器方法将生成如下响应：
HTTP/1.1 200 Ok
Content-Type: application/json; charset=utf-8
Date: Tue, 12 Dec 2017 16:16:04 GMT
Server: nginx/1.12.1
Content-Length: 225
Connection: Close
myCallbackFunction({<json>})
Script 标记从 JSONP 端点加载该响应，从而转变为执行 myCallbackFunction 函数。 攻击者可以使用其他回调名称导航 DOM 并与其交互。 例如，opener.document.body.someElemnt.firstChild.nextElementSibling.submit 可用于查找目标页面中的表格并进行提交。
def myJSONPService(callback: String) = Action {
val json = getJSONToBeReturned()
Ok(Jsonp(callback, json))
}
GET /api/latest.json?callback=myCallbackFunction 等请求，Example 1 中所述的控制器方法将生成如下响应：
HTTP/1.1 200 Ok
Content-Type: application/json; charset=utf-8
Date: Tue, 12 Dec 2017 16:16:04 GMT
Server: nginx/1.12.1
Content-Length: 225
Connection: Close
myCallbackFunction({<json>})
Script 标记从 JSONP 端点加载该响应，从而转变为执行 myCallbackFunction 函数。 攻击者可以使用其他回调名称导航 DOM 并与其交互。 例如，opener.document.body.someElemnt.firstChild.nextElementSibling.submit 可用于查找目标页面中的表格并进行提交。sanitizeValue 设置为 false 使得未经过处理的输入导致 Cross-Site Scripting 等漏洞。sanitizeValue 属性确定将值应用于 HTML 标记时是否运行 HTML 清理软件。输入可能直接来自用户，因此可能被视为不安全。由于多种原因，可以将 sanitizeValue 属性设置为 false，例如允许其他输入字符。但是，这样做可能会无意中导致在代码中执行不安全的用户输入。将 sanitizeValue 属性设置为 true（默认值）更为安全。RichTextEditor 将 sanitizeValue 属性设置为 false：
new RichTextEditor({
sanitizeValue: false,
value: input
}).placeAt("moreContent");
...
lv_uri = request->get_form_field( 'uri' ).
CALL METHOD cl_http_utility=>set_request_uri
EXPORTING
request = lo_request
uri = lv_uri.
...
http 或 https 的协议，类似于下面这样：
...
PageReference ref = ApexPages.currentPage();
Map<String,String> params = ref.getParameters();
HttpRequest req = new HttpRequest();
req.setEndpoint(params.get('url'));
HTTPResponse res = new Http().send(req);
http 或 https 的协议，类似于下面这样：
string url = Request.Form["url"];
HttpClient client = new HttpClient();
HttpResponseMessage response = await client.GetAsync(url);
http 或 https 的协议，类似于下面这样：
char *url = maliciousInput();
CURL *curl = curl_easy_init();
curl_easy_setopt(curl, CURLOPT_URL, url);
CURLcode res = curl_easy_perform(curl);
http 或 https 的协议，类似于下面这样：
...
final server = await HttpServer.bind('localhost', 18081);
server.listen((request) async {
final headers = request.headers;
final url = headers.value('url');
final client = IOClient();
final response = await client.get(Uri.parse(url!));
...
}
http 或 https 的协议，类似于下面这样：
url := request.Form.Get("url")
res, err =: http.Get(url)
...
http 或 https 的协议，类似于下面这样：
String url = request.getParameter("url");
CloseableHttpClient httpclient = HttpClients.createDefault();
HttpGet httpGet = new HttpGet(url);
CloseableHttpResponse response1 = httpclient.execute(httpGet);
http 或 https 的协议，类似于下面这样：
var http = require('http');
var url = require('url');
function listener(request, response){
var request_url = url.parse(request.url, true)['query']['url'];
http.request(request_url)
...
}
...
http.createServer(listener).listen(8080);
...
http 或 https 的协议，类似于下面这样：
val url: String = request.getParameter("url")
val httpclient: CloseableHttpClient = HttpClients.createDefault()
val httpGet = HttpGet(url)
val response1: CloseableHttpResponse = httpclient.execute(httpGet)
http 或 https 的协议，类似于下面这样：
$url = $_GET['url'];
$c = curl_init();
curl_setopt($c, CURLOPT_POST, 0);
curl_setopt($c,CURLOPT_URL,$url);
$response=curl_exec($c);
curl_close($c);
http 或 https 的协议，类似于下面这样：
url = request.GET['url']
handle = urllib.urlopen(url)
http 或 https 的协议，类似于下面这样：
url = req['url']
Net::HTTP.get(url)
http 或 https 的协议，类似于下面这样：
def getFile(url: String) = Action { request =>
...
val url = request.body.asText.getOrElse("http://google.com")
ws.url(url).get().map { response =>
Ok(s"Request sent to $url")
}
...
}
http 或 https 的协议，类似于下面这样：
// Set up the context data
VelocityContext context = new VelocityContext();
context.put( "name", user.name );
// Load the template
String template = getUserTemplateFromRequestBody(request);
RuntimeServices runtimeServices = RuntimeSingleton.getRuntimeServices();
StringReader reader = new StringReader(template);
SimpleNode node = runtimeServices.parse(reader, "myTemplate");
template = new Template();
template.setRuntimeServices(runtimeServices);
template.setData(node);
template.initDocument();
// Render the template with the context data
StringWriter sw = new StringWriter();
template.merge( context, sw );
Example 1 使用 Velocity 作为模板引擎。对于该引擎，攻击者可以提交以下模板以在服务器上运行任意命令：
$name.getClass().forName("java.lang.Runtime").getRuntime().exec(<COMMAND>)
app.get('/', function(req, res){
var template = _.template(req.params['template']);
res.write("<html><body><h2>Hello World!</h2>" + template() + "</body></html>");
});
Example 1 会使用 Underscore.js 作为 Node.js 应用程序中的模板引擎。对于该引擎，攻击者可以提交以下模板以在服务器上运行任意命令：
<% cp = process.mainModule.require('child_process');cp.exec(<COMMAND>); %>
Jinja2 模板引擎呈现该模板。
from django.http import HttpResponse
from jinja2 import Template as Jinja2_Template
from jinja2 import Environment, DictLoader, escape
def process_request(request):
# Load the template
template = request.GET['template']
t = Jinja2_Template(template)
name = source(request.GET['name'])
# Render the template with the context data
html = t.render(name=escape(name))
return HttpResponse(html)
Example 1 使用 Jinja2 作为模板引擎。对于该引擎，攻击者可以提交以下模板以从服务器中读取任意文件：示例 2：以下示例显示了如何从 HTTP 请求中检索模板并使用
template={{''.__class__.__mro__[2].__subclasses__()[40]('/etc/passwd').read()}}
Django 模板引擎呈现该模板。
from django.http import HttpResponse
from django.template import Template, Context, Engine
def process_request(request):
# Load the template
template = source(request.GET['template'])
t = Template(template)
user = {"name": "John", "secret":getToken()}
ctx = Context(locals())
html = t.render(ctx)
return HttpResponse(html)
Example 2 使用 Django 作为模板引擎。对于该引擎，攻击者将无法执行任意命令，但他们能够访问模板上下文中的所有对象。在此示例中，上下文中存在密钥标记，该密钥标记可能会被攻击者泄露。@SessionAttributes 标注的类意味着，Spring 会将更改复制到会话对象中的模型属性。如果攻击者能够在模型属性中存储任意值，这些更改将在会话对象中复制，并可能得到应用程序信任。如果会话属性使用用户应当无法修改的可信赖数据进行初始化，攻击者则能够实施 Session Puzzling 攻击，滥用应用程序逻辑。
@Controller
@SessionAttributes("user")
public class HomeController {
...
@RequestMapping(value= "/auth", method=RequestMethod.POST)
public String authHandler(@RequestParam String username, @RequestParam String password, RedirectAttributes attributes, Model model) {
User user = userService.findByNamePassword(username, password);
if (user == null) {
// Handle error
...
} else {
// Handle success
attributes.addFlashAttribute("user", user);
return "redirect:home";
}
}
...
}
User 实例，因为此类使用 @SessionAttributes("user") 标注，并使用它来验证密码重置问题。
@Controller
@SessionAttributes("user")
public class ResetPasswordController {
@RequestMapping(value = "/resetQuestion", method = RequestMethod.POST)
public String resetQuestionHandler(@RequestParam String answerReset, SessionStatus status, User user, Model model) {
if (!user.getAnswer().equals(answerReset)) {
// Handle error
...
} else {
// Handle success
...
}
}
}
user 实例，此会话是在登录过程中存储实例的位置。然而，Spring 将检查请求，并且尝试将其数据绑定到模型 user 实例。如果接收的请求包含可绑定到 User 类的数据，Spring 会将接收的数据合并到用户会话属性中。通过在 answerReset 查询参数中提交任意答案并提交相同值覆盖会话中存储的值，可以滥用这种情况。这样，攻击者可以为随机用户设置任意新密码。
...
taintedConnectionStr = request->get_form_field( 'dbconn_name' ).
TRY.
DATA(con) = cl_sql_connection=>get_connection( `R/3*` && taintedConnectionStr ).
...
con->close( ).
CATCH cx_sql_exception INTO FINAL(exc).
...
ENDTRY.
...
sethostid(argv[1]);
...
sethostid()，但是未被赋予权限的用户也可能会调用这个程序。这个例子中的代码允许用户输入直接控制系统设置的值。如果攻击者为主机 ID 提供一个恶意值，攻击者会错误地识别网络上受影响的机器或者引发其他一些意料之外的行为。
...
ACCEPT OPT1.
ACCEPT OPT2
COMPUTE OPTS = OPT1 + OPT2.
CALL 'MQOPEN' USING HCONN, OBJECTDESC, OPTS, HOBJ, COMPOCODE REASON.
...
...
<cfset code = SetProfileString(IniPath,
Section, "timeout", Form.newTimeout)>
...
Form.newTimeout 的值用于指定超时时间，因此攻击者可以通过指定一个超大数值来发起 denial of service (DoS)，从而破坏应用程序的正常运行。
...
catalog := request.Form.Get("catalog")
path := request.Form.Get("path")
os.Setenv(catalog, path)
...
HttpServletRequest 中读取一个字符串，并将该字符串设置为数据库 Connection 中的当前目录。
...
conn.setCatalog(request.getParamter("catalog"));
...
http.IncomingMessage 请求变量中读取字符串，并使用该字符串设置其他 V8 命令行标记。
var v8 = require('v8');
...
var flags = url.parse(request.url, true)['query']['flags'];
...
v8.setFlagsFromString(flags);
...
<?php
...
$table_name=$_GET['catalog'];
$retrieved_array = pg_copy_to($db_connection, $table_name);
...
?>
...
catalog = request.GET['catalog']
path = request.GET['path']
os.putenv(catalog, path)
...
Connection 的当前目录。
def connect(catalog: String) = Action { request =>
...
conn.setCatalog(catalog)
...
}
...
sqlite3(SQLITE_CONFIG_LOG, user_controllable);
...
Request 对象中读取一个字符串，并将该字符串设置为数据库 Connection 中的当前目录。
...
Dim conn As ADODB.Connection
Set conn = New ADODB.Connection
Dim rsTables As ADODB.Recordset
Dim Catalog As New ADOX.Catalog
Set Catalog.ActiveConnection = conn
Catalog.Create Request.Form("catalog")
...
myModule.config(function($compileProvider){
$compileProvider.imgSrcSanitizationWhitelist(userInput);
});
/^(http(s)?|javascript):.*/，应用程序可能会允许在图像源 URL 中使用内联 JavaScript，这可能会引发 cross-site scripting 攻击。ProcessWorkitemRequest.setAction() 调用中的批准操作。
void processRequest() {
String workItemId = ApexPages.currentPage().getParameters().get('Id');
String action = ApexPages.currentPage().getParameters().get('Action');
Approval.ProcessWorkitemRequest req = new Approval.ProcessWorkitemRequest();
req.setWorkitemId(workItemId);
req.setAction(action);
Approval.ProcessResult res = Approval.process(req);
...
}
var hash = window.location.hash;
var myStartSymbol = decodeURIComponent(hash.substring(1, hash.length));
myModule.config(function($interpolateProvider){
$interpolateProvider.startSymbol(myStartSymbol);
});
...
public String inputValue {
get { return inputValue; }
set { inputValue = value; }
}
...
String queryString = 'SELECT Id FROM Contact WHERE (IsDeleted = false AND Name like \'%' + inputValue + '%\')';
result = Database.query(queryString);
...
SELECT Id FROM Contact WHERE (IsDeleted = false AND Name like '%inputValue%')
inputValue 不包含单引号字符时，才会正确执行这一查询。如果攻击者为 inputValue 输入字符串 name') OR (Name like '%，则该查询会变成：
SELECT Id FROM Contact WHERE (IsDeleted = false AND Name like '%name') OR (Name like '%%')
name') OR (Name like '% 会使 where 子句使用 LIKE '%%' 条件，这将强制该查询输出所有可能的 ID 值，因为它在逻辑上将等同于一个更为简化的查询：
SELECT Id FROM Contact WHERE ... OR (Name like '%%')
...
public String inputValue {
get { return inputValue; }
set { inputValue = value; }
}
...
String queryString = 'Name LIKE \'%' + inputValue + '%\'';
String searchString = 'Acme';
String searchQuery = 'FIND :searchString IN ALL FIELDS RETURNING Contact (Id WHERE ' + queryString + ')';
List<List<SObject>> results = Search.query(searchQuery);
...
String searchQuery = 'FIND :searchString IN ALL FIELDS RETURNING Contact (Id WHERE Name LIKE '%' + inputValue + '%')';
inputValue 不包含单引号字符时，才会正确执行这一查询。如果攻击者为 inputValue 输入字符串 1%' OR Name LIKE '，则该查询会变成：
String searchQuery = 'FIND :searchString IN ALL FIELDS RETURNING Contact (Id WHERE Name LIKE '%1%' OR Name LIKE '%%')';
OR Name like '%%' 会使 where 子句使用 LIKE '%%' 条件，这将强制该查询输出所有包含“map”短语的记录，因为它在逻辑上将等同于一个更为简化的查询：
FIND 'map*' IN ALL FIELDS RETURNING Contact (Id WHERE Name LIKE '%%')
String beans = getBeanDefinitionFromUser();
GenericApplicationContext ctx = new GenericApplicationContext();
XmlBeanDefinitionReader xmlReader = new XmlBeanDefinitionReader(ctx);
xmlReader.loadBeanDefinitions(new UrlResource(beans));
ctx.refresh();
<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="3.0"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" metadata-complete="true">
...
<context-param>
<param-name>defaultHtmlEscape</param-name>
<param-value>false</param-value>
</context-param>
...
</web-app>
...
v_account = request->get_form_field( 'account' ).
v_reference = request->get_form_field( 'ref_key' ).
CONCATENATE `user = '` sy-uname `'` INTO cl_where.
IF v_account IS NOT INITIAL.
CONCATENATE cl_where ` AND account = ` v_account INTO cl_where SEPARATED BY SPACE.
ENDIF.
IF v_reference IS NOT INITIAL.
CONCATENATE cl_where "AND ref_key = `" v_reference "`" INTO cl_where.
ENDIF.
SELECT *
FROM invoice_items
INTO CORRESPONDING FIELDS OF TABLE itab_items
WHERE (cl_where).
...
SELECT *
FROM invoice_items
INTO CORRESPONDING FIELDS OF TABLE itab_items
WHERE user = sy-uname
AND account = <account>
AND ref_key = <reference>.
"abc` OR MANDT NE `+"，为 v_account 输入字符串“1000”，则该查询会变成：
SELECT *
FROM invoice_items
INTO CORRESPONDING FIELDS OF TABLE itab_items
WHERE user = sy-uname
AND account = 1000
AND ref_key = `abc` OR MANDT NE `+`.
OR MANDT NE `+` 条件会导致 WHERE 子句的估值永远为 true，因为，客户端字段永远不会等于 literal +，因此该查询在逻辑上等同于一个更为简化的查询：
SELECT * FROM invoice_items
INTO CORRESPONDING FIELDS OF TABLE itab_items.
invoice_items 表中的所有条目，而不论指定用户是谁。
PARAMETERS: p_street TYPE string,
p_city TYPE string.
Data: v_sql TYPE string,
stmt TYPE REF TO CL_SQL_STATEMENT.
v_sql = "UPDATE EMP_TABLE SET ".
"Update employee address. Build the update statement with changed details
IF street NE p_street.
CONCATENATE v_sql "STREET = `" p_street "`".
ENDIF.
IF city NE p_city.
CONCATENATE v_sql "CITY = `" p_city "`".
ENDIF.
l_upd = stmt->execute_update( v_sql ).
"ABC` SALARY = `1000000" 的字符串，则应用程序会使用修订后的薪资更新数据库！
...
var params:Object = LoaderInfo(this.root.loaderInfo).parameters;
var username:String = String(params["username"]);
var itemName:String = String(params["itemName"]);
var query:String = "SELECT * FROM items WHERE owner = " + username + " AND itemname = " + itemName;
stmt.sqlConnection = conn;
stmt.text = query;
stmt.execute();
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
owner 与被授予权限的当前用户一致的条目。
...
string userName = ctx.getAuthenticatedUserName();
string query = "SELECT * FROM items WHERE owner = '"
+ userName + "' AND itemname = '"
+ ItemName.Text + "'";
sda = new SqlDataAdapter(query, conn);
DataTable dt = new DataTable();
sda.Fill(dt);
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'); DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
例 2：此外，SQLite 使用以下代码可以获得类似的结果：
...
ctx.getAuthUserName(&userName); {
CString query = "SELECT * FROM items WHERE owner = '"
+ userName + "' AND itemname = '"
+ request.Lookup("item") + "'";
dbms.ExecuteSQL(query);
...
...
sprintf (sql, "SELECT * FROM items WHERE owner='%s' AND itemname='%s'", username, request.Lookup("item"));
printf("SQL to execute is: \n\t\t %s\n", sql);
rc = sqlite3_exec(db,sql, NULL,0, &err);
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'); DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
...
ACCEPT USER.
ACCEPT ITM.
MOVE "SELECT * FROM items WHERE owner = '" TO QUERY1.
MOVE "' AND itemname = '" TO QUERY2.
MOVE "'" TO QUERY3.
STRING
QUERY1, USER, QUERY2, ITM, QUERY3 DELIMITED BY SIZE
INTO QUERY
END-STRING.
EXEC SQL
EXECUTE IMMEDIATE :QUERY
END-EXEC.
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itm 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 条件会导致 where 子句的估值永远为 true，因此该查询在逻辑上等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
...
<cfquery name="matchingItems" datasource="cfsnippets">
SELECT * FROM items
WHERE owner='#Form.userName#'
AND itemId=#Form.ID#
</cfquery>
...
SELECT * FROM items
WHERE owner = <userName>
AND itemId = <ID>;
Form.ID 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 Form.ID 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemId = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 hacker 的攻击者为 Form.ID 输入字符串“hacker'); DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'hacker'
AND itemId = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'hacker'
AND itemId = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
...
final server = await HttpServer.bind('localhost', 18081);
server.listen((request) async {
final headers = request.headers;
final userName = headers.value('userName');
final itemName = headers.value('itemName');
final query = "SELECT * FROM items WHERE owner = '"
+ userName! + "' AND itemname = '"
+ itemName! + "'";
db.query(query);
}
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，该查询才能正常运行。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，则该查询会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a'，where 子句的值将始终为 true，这样该查询在逻辑上就等同于一个更为简单的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1 中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
...
rawQuery := request.URL.Query()
username := rawQuery.Get("userName")
itemName := rawQuery.Get("itemName")
query := "SELECT * FROM items WHERE owner = " + username + " AND itemname = " + itemName + ";"
db.Exec(query)
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，该查询才能正常运行。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，则该查询会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a'，where 子句的值将始终为 true，这样该查询在逻辑上就等同于一个更为简单的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1 中所用的技巧进行攻击。如果攻击者输入字符串 "name'; DELETE FROM items; SELECT * FROM items WHERE 'a'='a"，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
...
String userName = ctx.getAuthenticatedUserName();
String itemName = request.getParameter("itemName");
String query = "SELECT * FROM items WHERE owner = '"
+ userName + "' AND itemname = '"
+ itemName + "'";
ResultSet rs = stmt.execute(query);
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
Example 1 以适应 Android 平台。
...
PasswordAuthentication pa = authenticator.getPasswordAuthentication();
String userName = pa.getUserName();
String itemName = this.getIntent().getExtras().getString("itemName");
String query = "SELECT * FROM items WHERE owner = '"
+ userName + "' AND itemname = '"
+ itemName + "'";
SQLiteDatabase db = this.openOrCreateDatabase("DB", MODE_PRIVATE, null);
Cursor c = db.rawQuery(query, null);
...
...
var username = document.form.username.value;
var itemName = document.form.itemName.value;
var query = "SELECT * FROM items WHERE owner = " + username + " AND itemname = " + itemName + ";";
db.transaction(function (tx) {
tx.executeSql(query);
}
)
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
...
$userName = $_SESSION['userName'];
$itemName = $_POST['itemName'];
$query = "SELECT * FROM items WHERE owner = '$userName' AND itemname = '$itemName';";
$result = mysql_query($query);
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
procedure get_item (
itm_cv IN OUT ItmCurTyp,
usr in varchar2,
itm in varchar2)
is
open itm_cv for ' SELECT * FROM items WHERE ' ||
'owner = '''|| usr || '''' ||
' AND itemname = ''' || itm || '''';
end get_item;
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itm 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 条件会导致 where 子句的估值永远为 true，因此该查询在逻辑上等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
...
userName = req.field('userName')
itemName = req.field('itemName')
query = "SELECT * FROM items WHERE owner = ' " + userName +" ' AND itemname = ' " + itemName +"';"
cursor.execute(query)
result = cursor.fetchall()
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
...
userName = getAuthenticatedUserName()
itemName = params[:itemName]
sqlQuery = "SELECT * FROM items WHERE owner = '#{userName}' AND itemname = '#{itemName}'"
rs = conn.query(sqlQuery)
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。
...
id = params[:id]
itemName = Mysql.escape_string(params[:itemName])
sqlQuery = "SELECT * FROM items WHERE id = #{userName} AND itemname = '#{itemName}'"
rs = conn.query(sqlQuery)
...
SELECT * FROM items WHERE id=<id> AND itemname = <itemName>;
itemName 中指定单引号，并且似乎已经避免了 SQL injection 漏洞。然而，由于 Ruby 不是静态类型语言，即使我们期望 id 是某种整数，因为这是通过用户输入来指定的，它也不一定是一个数字。如果攻击者可以将 id 的值更改为 1 OR id!=1--，因为没有检查 id 实际上是数字，SQL 查询现在变为：
SELECT * FROM items WHERE id=1 OR id!=1-- AND itemname = 'anyValue';
SELECT * FROM items WHERE id=1 OR id!=1;
id 的值是否等于 1，这当然相当于表中的一切内容。
def doSQLQuery(value:String) = Action.async { implicit request =>
val result: Future[Seq[User]] = db.run {
sql"select * from users where name = '#$value'".as[User]
}
...
}
SELECT * FROM users
WHERE name = <userName>
userName 不包含单引号字符时，该查询才能正常运行。 如果一个用户名为 wiley 的攻击者为 userName 输入字符串“name' OR 'a'='a”，则该查询会变成：
SELECT * FROM users
WHERE name = 'name' OR 'a'='a';
OR 'a'='a'，where 子句的值将始终为 true，这样该查询在逻辑上就等同于一个更为简单的查询：
SELECT * FROM users;
users 表中存储的所有条目，而不论其指定用户是谁。owner与当前经过身份验证的用户的名称一致的条目。
...
let queryStatementString = "SELECT * FROM items WHERE owner='\(username)' AND itemname='\(item)'"
var queryStatement: OpaquePointer? = nil
if sqlite3_prepare_v2(db, queryStatementString, -1, &queryStatement, nil) == SQLITE_OK {
if sqlite3_step(queryStatement) == SQLITE_ROW {
...
}
}
...
SELECT * FROM items
WHERE owner = '<userName>'
AND itemname = '<itemName>'
itemName不包含单引号字符时，该查询才能正常运行。如果一个用户名为 wiley的攻击者为 itemName 输入字符串“name' OR 'a'='a”，则该查询会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a'，where 子句的值将始终为 true，这样该查询在逻辑上就等同于一个更为简单的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'); DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
...
username = Session("username")
itemName = Request.Form("itemName")
strSQL = "SELECT * FROM items WHERE owner = '"& userName &"' AND itemname = '" & itemName &"'"
objRecordSet.Open strSQL, strConnect, adOpenDynamic, adLockOptimistic, adCmdText
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。Example 1.中构造和执行的查询所带来的影响。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name'; DELETE FROM items; --”，则该查询就会变为以下两个查询：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
--'
Example 1.中所用的技巧进行攻击。如果攻击者输入字符串“name'); DELETE FROM items; SELECT * FROM items WHERE 'a'='a”，将创建以下三个有效语句：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name';
DELETE FROM items;
SELECT * FROM items WHERE 'a'='a';
owner 与被授予权限的当前用户一致的条目。
...
string userName = ctx.getAuthenticatedUserName();
string queryString = "SELECT * FROM items WHERE owner = '"
+ userName + "' AND itemname = '"
+ ItemName.Text + "'";
SimpleQuery<Item> queryObject = new SimpleQuery(queryString);
Item[] items = (Item[])queryObject.Execute(query);
...
SELECT * FROM items
WHERE owner = <userName>
AND itemname = <itemName>;
itemName 不包含单引号字符时，才会正确执行这一查询。如果一个用户名为 wiley 的攻击者为 itemName 输入字符串“name' OR 'a'='a”，那么查询就会变成：
SELECT * FROM items
WHERE owner = 'wiley'
AND itemname = 'name' OR 'a'='a';
OR 'a'='a' 会使 where 从句永远评估为 true，因此该查询在逻辑上将等同于一个更为简化的查询：
SELECT * FROM items;
items 表中的所有条目，而不论其指定所有者是谁。