Search Results

Search found 497 results on 20 pages for 'xss prevention'.

Page 10/20 | < Previous Page | 6 7 8 9 10 11 12 13 14 15 16 17  | Next Page >

  • Implementing a "flag as spam/offensive" system

    - by UltraVi01
    I am looking for a community moderated way of managing/eliminating spam and offensive content. Functionality similar to StackOverflow and many other sites seems like a good way to go. Although I'm sure this could greatly vary based on specific needs, I am curious about the backend mechanism/algorithm --that is, has anyone had success using something like "3 strikes and you're out" -- the flagged post is automatically closed/deleted after 3 reports by users with the required credentials. Would something like this likely be effective or would it require a more complex solution to ensure honesty and effectiveness. Any thoughts / experiences would be great

    Read the article

  • PHP Security checklist (injection, sessions etc)

    - by NoviceCoding
    So what kind of things should a person using PHP and MySql be focused on to maximize security. Things I have done: -mysql_real_escape_string all inputs -validate all inputs after escaping em -Placed random alpha numerics before my table names -50character salt + Ripemd passwords Heres where I think I am slacking: -I know know nothing about sessions and securing them. How unsafe/safe is it if all you are doing is: session_start(); $_SESSION['login']= $login; and checking it with: session_start(); if(isset($_SESSION['login'])){ -I heard something about other forms of injection like cross site injection and what not... -And probably many other things I dont know about. Is there a "checklist"/Quicktut on making php secure? I dont even know what I should be worried about.I kinda regret now not building off cakephp since I am not a pro.

    Read the article

  • Preventing decompilation of C# application

    - by Kalpak
    Hi, We are planning to develop a client server application using C# and MySQL. We plan to sell the product on the shelf like any other software utility. We are worried about the decompilation of our product which does have some sort of edge over our competitors in terms of usability and bundled functionality. How can we prevent our software from decompilation, so the business logic of the product remains intact? We have heard about Reflector and other decompilers which makes our code very much vulnerable for copying. Our customer base is not Corporates by medical practitioners who themselves may not do it but our competitors may want to copy/disable licensing so value of our software goes down. Any suggestion to prevent this is most welcome. regards.. Obelisk

    Read the article

  • Imposing email limits on web page

    - by Martin
    To avoid spammers, what's a good strategy for imposing limits on users when sending email from our site? A count limit per day on individual IPs? Sender emails? Domains? In general terms, but recommended figures will also be helpful. Our users can send emails through our web page. They can register and log in but are also allowed to do this without logging in, but with a captcha and with a field for the senders email. Certainly, there is a header, "The user has sent you the following message.", limiting the use for spammers, so perhaps it's not a big problem. Any comments on what I'm doing will be greatly appreciated.

    Read the article

  • How can I cut down on this spam, and what is the point of it anyway?

    - by Steven
    I run a small, niche personal ads site. People post ads and then other people reply to them, which sends an email to the original creator of the ad telling them that someone is interested and giving them contact information for that interested person. Lately there's been some weird spam. People are receiving nonsense replies to their ads. Here is an example of one: Name: xkauwvyr Reply: vRYmbI <a href="http://rypmoxdkfblf.com/">rypmoxdkfblf</a>, url=http://pnjlwvhizwbq.com/]pnjlwvhizwbq[/url], [link=http://hmenwoujxrfv.com/]hmenwoujxrfv[/link], http://ogsekuhoyeud.com/ They vary in length and composition but they all look roughly like that. The first idea I had was to simply throw out any reply that contained the string " Also, is this spam just some ass playing a trick on my website, or is it something more malicious?

    Read the article

  • Adding the New HTML Editor Extender to a Web Forms Application using NuGet

    - by Stephen Walther
    The July 2011 release of the Ajax Control Toolkit includes a new, lightweight, HTML5 compatible HTML Editor extender. In this blog entry, I explain how you can take advantage of NuGet to quickly add the new HTML Editor control extender to a new or existing ASP.NET Web Forms application. Installing the Latest Version of the Ajax Control Toolkit with NuGet NuGet is a package manager. It enables you to quickly install new software directly from within Visual Studio 2010. You can use NuGet to install additional software when building any type of .NET application including ASP.NET Web Forms and ASP.NET MVC applications. If you have not already installed NuGet then you can install NuGet by navigating to the following address and clicking the giant install button: http://nuget.org/ After you install NuGet, you can add the Ajax Control Toolkit to a new or existing ASP.NET Web Forms application by selecting the Visual Studio menu option Tools, Library Package Manager, Package Manager Console: Selecting this menu option opens the Package Manager Console. You can enter the command Install-Package AjaxControlToolkit in the console to install the Ajax Control Toolkit: After you install the Ajax Control Toolkit with NuGet, your application will include an assembly reference to the AjaxControlToolkit.dll and SanitizerProviders.dll assemblies: Furthermore, your Web.config file will be updated to contain a new tag prefix for the Ajax Control Toolkit controls: <configuration> <system.web> <compilation debug="true" targetFramework="4.0" /> <pages> <controls> <add tagPrefix="ajaxToolkit" assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" /> </controls> </pages> </system.web> </configuration> The configuration file installed by NuGet adds the prefix ajaxToolkit for all of the Ajax Control Toolkit controls. You can type ajaxToolkit: in source view to get auto-complete in Source view. You can, of course, change this prefix to anything you want. Using the HTML Editor Extender After you install the Ajax Control Toolkit, you can use the HTML Editor Extender with the standard ASP.NET TextBox control to enable users to enter rich formatting such as bold, underline, italic, different fonts, and different background and foreground colors. For example, the following page can be used for entering comments. The page contains a standard ASP.NET TextBox, Button, and Label control. When you click the button, any text entered into the TextBox is displayed in the Label control. It is a pretty boring page: Let’s make this page fancier by extending the standard ASP.NET TextBox with the HTML Editor extender control: Notice that the ASP.NET TextBox now has a toolbar which includes buttons for performing various kinds of formatting. For example, you can change the size and font used for the text. You also can change the foreground and background color – and make many other formatting changes. You can customize the toolbar buttons which the HTML Editor extender displays. To learn how to customize the toolbar, see the HTML Editor Extender sample page here: http://www.asp.net/ajaxLibrary/AjaxControlToolkitSampleSite/HTMLEditorExtender/HTMLEditorExtender.aspx Here’s the source code for the ASP.NET page: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebApplication1.Default" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title>Add Comments</title> </head> <body> <form id="form1" runat="server"> <div> <ajaxToolkit:ToolkitScriptManager ID="TSM1" runat="server" /> <asp:TextBox ID="txtComments" TextMode="MultiLine" Columns="50" Rows="8" Runat="server" /> <ajaxToolkit:HtmlEditorExtender ID="hee" TargetControlID="txtComments" Runat="server" /> <br /><br /> <asp:Button ID="btnSubmit" Text="Add Comment" Runat="server" onclick="btnSubmit_Click" /> <hr /> <asp:Label ID="lblComment" Runat="server" /> </div> </form> </body> </html> Notice that the page above contains 5 controls. The page contains a standard ASP.NET TextBox, Button, and Label control. However, the page also contains an Ajax Control Toolkit ToolkitScriptManager control and HtmlEditorExtender control. The HTML Editor extender control extends the standard ASP.NET TextBox control. The HTML Editor TargetID attribute points at the TextBox control. Here’s the code-behind for the page above:   using System; namespace WebApplication1 { public partial class Default : System.Web.UI.Page { protected void btnSubmit_Click(object sender, EventArgs e) { lblComment.Text = txtComments.Text; } } }   Preventing XSS/JavaScript Injection Attacks If you use an HTML Editor -- any HTML Editor -- in a public facing web page then you are opening your website up to Cross-Site Scripting (XSS) attacks. An evil hacker could submit HTML using the HTML Editor which contains JavaScript that steals private information such as other user’s passwords. Imagine, for example, that you create a web page which enables your customers to post comments about your website. Furthermore, imagine that you decide to redisplay the comments so every user can see them. In that case, a malicious user could submit JavaScript which displays a dialog asking for a user name and password. When an unsuspecting customer enters their secret password, the script could transfer the password to the hacker’s website. So how do you accept HTML content without opening your website up to JavaScript injection attacks? The Ajax Control Toolkit HTML Editor supports the Anti-XSS library. You can use the Anti-XSS library to sanitize any HTML content. The Anti-XSS library, for example, strips away all JavaScript automatically. You can download the Anti-XSS library from NuGet. Open the Package Manager Console and execute the command Install-Package AntiXSS: Adding the Anti-XSS library to your application adds two assemblies to your application named AntiXssLibrary.dll and HtmlSanitizationLibrary.dll. After you install the Anti-XSS library, you can configure the HTML Editor extender to use the Anti-XSS library your application’s web.config file: <?xml version="1.0" encoding="utf-8"?> <configuration> <configSections> <sectionGroup name="system.web"> <section name="sanitizer" requirePermission="false" type="AjaxControlToolkit.Sanitizer.ProviderSanitizerSection, AjaxControlToolkit"/> </sectionGroup> </configSections> <system.web> <sanitizer defaultProvider="AntiXssSanitizerProvider"> <providers> <add name="AntiXssSanitizerProvider" type="AjaxControlToolkit.Sanitizer.AntiXssSanitizerProvider"></add> </providers> </sanitizer> <compilation debug="true" targetFramework="4.0" /> <pages> <controls> <add tagPrefix="ajaxToolkit" assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" /> </controls> </pages> </system.web> </configuration> Summary In this blog entry, I described how you can quickly get started using the new HTML Editor extender – included with the July 2011 release of the Ajax Control Toolkit – by installing the Ajax Control Toolkit with NuGet. If you want to learn more about the HTML Editor then please take a look at the Ajax Control Toolkit sample site: http://www.asp.net/ajaxLibrary/AjaxControlToolkitSampleSite/HTMLEditorExtender/HTMLEditorExtender.aspx

    Read the article

  • Security Issues with Single Page Apps

    - by Stephen.Walther
    Last week, I was asked to do a code review of a Single Page App built using the ASP.NET Web API, Durandal, and Knockout (good stuff!). In particular, I was asked to investigate whether there any special security issues associated with building a Single Page App which are not present in the case of a traditional server-side ASP.NET application. In this blog entry, I discuss two areas in which you need to exercise extra caution when building a Single Page App. I discuss how Single Page Apps are extra vulnerable to both Cross-Site Scripting (XSS) attacks and Cross-Site Request Forgery (CSRF) attacks. This goal of this blog post is NOT to persuade you to avoid writing Single Page Apps. I’m a big fan of Single Page Apps. Instead, the goal is to ensure that you are fully aware of some of the security issues related to Single Page Apps and ensure that you know how to guard against them. Cross-Site Scripting (XSS) Attacks According to WhiteHat Security, over 65% of public websites are open to XSS attacks. That’s bad. By taking advantage of XSS holes in a website, a hacker can steal your credit cards, passwords, or bank account information. Any website that redisplays untrusted information is open to XSS attacks. Let me give you a simple example. Imagine that you want to display the name of the current user on a page. To do this, you create the following server-side ASP.NET page located at http://MajorBank.com/SomePage.aspx: <%@Page Language="C#" %> <html> <head> <title>Some Page</title> </head> <body> Welcome <%= Request["username"] %> </body> </html> Nothing fancy here. Notice that the page displays the current username by using Request[“username”]. Using Request[“username”] displays the username regardless of whether the username is present in a cookie, a form field, or a query string variable. Unfortunately, by using Request[“username”] to redisplay untrusted information, you have now opened your website to XSS attacks. Here’s how. Imagine that an evil hacker creates the following link on another website (hackers.com): <a href="/SomePage.aspx?username=<script src=Evil.js></script>">Visit MajorBank</a> Notice that the link includes a query string variable named username and the value of the username variable is an HTML <SCRIPT> tag which points to a JavaScript file named Evil.js. When anyone clicks on the link, the <SCRIPT> tag will be injected into SomePage.aspx and the Evil.js script will be loaded and executed. What can a hacker do in the Evil.js script? Anything the hacker wants. For example, the hacker could display a popup dialog on the MajorBank.com site which asks the user to enter their password. The script could then post the password back to hackers.com and now the evil hacker has your secret password. ASP.NET Web Forms and ASP.NET MVC have two automatic safeguards against this type of attack: Request Validation and Automatic HTML Encoding. Protecting Coming In (Request Validation) In a server-side ASP.NET app, you are protected against the XSS attack described above by a feature named Request Validation. If you attempt to submit “potentially dangerous” content — such as a JavaScript <SCRIPT> tag — in a form field or query string variable then you get an exception. Unfortunately, Request Validation only applies to server-side apps. Request Validation does not help in the case of a Single Page App. In particular, the ASP.NET Web API does not pay attention to Request Validation. You can post any content you want – including <SCRIPT> tags – to an ASP.NET Web API action. For example, the following HTML page contains a form. When you submit the form, the form data is submitted to an ASP.NET Web API controller on the server using an Ajax request: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title></title> </head> <body> <form data-bind="submit:submit"> <div> <label> User Name: <input data-bind="value:user.userName" /> </label> </div> <div> <label> Email: <input data-bind="value:user.email" /> </label> </div> <div> <input type="submit" value="Submit" /> </div> </form> <script src="Scripts/jquery-1.7.1.js"></script> <script src="Scripts/knockout-2.1.0.js"></script> <script> var viewModel = { user: { userName: ko.observable(), email: ko.observable() }, submit: function () { $.post("/api/users", ko.toJS(this.user)); } }; ko.applyBindings(viewModel); </script> </body> </html> The form above is using Knockout to bind the form fields to a view model. When you submit the form, the view model is submitted to an ASP.NET Web API action on the server. Here’s the server-side ASP.NET Web API controller and model class: public class UsersController : ApiController { public HttpResponseMessage Post(UserViewModel user) { var userName = user.UserName; return Request.CreateResponse(HttpStatusCode.OK); } } public class UserViewModel { public string UserName { get; set; } public string Email { get; set; } } If you submit the HTML form, you don’t get an error. The “potentially dangerous” content is passed to the server without any exception being thrown. In the screenshot below, you can see that I was able to post a username form field with the value “<script>alert(‘boo’)</script”. So what this means is that you do not get automatic Request Validation in the case of a Single Page App. You need to be extra careful in a Single Page App about ensuring that you do not display untrusted content because you don’t have the Request Validation safety net which you have in a traditional server-side ASP.NET app. Protecting Going Out (Automatic HTML Encoding) Server-side ASP.NET also protects you from XSS attacks when you render content. By default, all content rendered by the razor view engine is HTML encoded. For example, the following razor view displays the text “<b>Hello!</b>” instead of the text “Hello!” in bold: @{ var message = "<b>Hello!</b>"; } @message   If you don’t want to render content as HTML encoded in razor then you need to take the extra step of using the @Html.Raw() helper. In a Web Form page, if you use <%: %> instead of <%= %> then you get automatic HTML Encoding: <%@ Page Language="C#" %> <% var message = "<b>Hello!</b>"; %> <%: message %> This automatic HTML Encoding will prevent many types of XSS attacks. It prevents <script> tags from being rendered and only allows &lt;script&gt; tags to be rendered which are useless for executing JavaScript. (This automatic HTML encoding does not protect you from all forms of XSS attacks. For example, you can assign the value “javascript:alert(‘evil’)” to the Hyperlink control’s NavigateUrl property and execute the JavaScript). The situation with Knockout is more complicated. If you use the Knockout TEXT binding then you get HTML encoded content. On the other hand, if you use the HTML binding then you do not: <!-- This JavaScript DOES NOT execute --> <div data-bind="text:someProp"></div> <!-- This Javacript DOES execute --> <div data-bind="html:someProp"></div> <script src="Scripts/jquery-1.7.1.js"></script> <script src="Scripts/knockout-2.1.0.js"></script> <script> var viewModel = { someProp : "<script>alert('Evil!')<" + "/script>" }; ko.applyBindings(viewModel); </script>   So, in the page above, the DIV element which uses the TEXT binding is safe from XSS attacks. According to the Knockout documentation: “Since this binding sets your text value using a text node, it’s safe to set any string value without risking HTML or script injection.” Just like server-side HTML encoding, Knockout does not protect you from all types of XSS attacks. For example, there is nothing in Knockout which prevents you from binding JavaScript to a hyperlink like this: <a data-bind="attr:{href:homePageUrl}">Go</a> <script src="Scripts/jquery-1.7.1.min.js"></script> <script src="Scripts/knockout-2.1.0.js"></script> <script> var viewModel = { homePageUrl: "javascript:alert('evil!')" }; ko.applyBindings(viewModel); </script> In the page above, the value “javascript:alert(‘evil’)” is bound to the HREF attribute using Knockout. When you click the link, the JavaScript executes. Cross-Site Request Forgery (CSRF) Attacks Cross-Site Request Forgery (CSRF) attacks rely on the fact that a session cookie does not expire until you close your browser. In particular, if you visit and login to MajorBank.com and then you navigate to Hackers.com then you will still be authenticated against MajorBank.com even after you navigate to Hackers.com. Because MajorBank.com cannot tell whether a request is coming from MajorBank.com or Hackers.com, Hackers.com can submit requests to MajorBank.com pretending to be you. For example, Hackers.com can post an HTML form from Hackers.com to MajorBank.com and change your email address at MajorBank.com. Hackers.com can post a form to MajorBank.com using your authentication cookie. After your email address has been changed, by using a password reset page at MajorBank.com, a hacker can access your bank account. To prevent CSRF attacks, you need some mechanism for detecting whether a request is coming from a page loaded from your website or whether the request is coming from some other website. The recommended way of preventing Cross-Site Request Forgery attacks is to use the “Synchronizer Token Pattern” as described here: https://www.owasp.org/index.php/Cross-Site_Request_Forgery_%28CSRF%29_Prevention_Cheat_Sheet When using the Synchronizer Token Pattern, you include a hidden input field which contains a random token whenever you display an HTML form. When the user opens the form, you add a cookie to the user’s browser with the same random token. When the user posts the form, you verify that the hidden form token and the cookie token match. Preventing Cross-Site Request Forgery Attacks with ASP.NET MVC ASP.NET gives you a helper and an action filter which you can use to thwart Cross-Site Request Forgery attacks. For example, the following razor form for creating a product shows how you use the @Html.AntiForgeryToken() helper: @model MvcApplication2.Models.Product <h2>Create Product</h2> @using (Html.BeginForm()) { @Html.AntiForgeryToken(); <div> @Html.LabelFor( p => p.Name, "Product Name:") @Html.TextBoxFor( p => p.Name) </div> <div> @Html.LabelFor( p => p.Price, "Product Price:") @Html.TextBoxFor( p => p.Price) </div> <input type="submit" /> } The @Html.AntiForgeryToken() helper generates a random token and assigns a serialized version of the same random token to both a cookie and a hidden form field. (Actually, if you dive into the source code, the AntiForgeryToken() does something a little more complex because it takes advantage of a user’s identity when generating the token). Here’s what the hidden form field looks like: <input name=”__RequestVerificationToken” type=”hidden” value=”NqqZGAmlDHh6fPTNR_mti3nYGUDgpIkCiJHnEEL59S7FNToyyeSo7v4AfzF2i67Cv0qTB1TgmZcqiVtgdkW2NnXgEcBc-iBts0x6WAIShtM1″ /> And here’s what the cookie looks like using the Google Chrome developer toolbar: You use the [ValidateAntiForgeryToken] action filter on the controller action which is the recipient of the form post to validate that the token in the hidden form field matches the token in the cookie. If the tokens don’t match then validation fails and you can’t post the form: public ActionResult Create() { return View(); } [ValidateAntiForgeryToken] [HttpPost] public ActionResult Create(Product productToCreate) { if (ModelState.IsValid) { // save product to db return RedirectToAction("Index"); } return View(); } How does this all work? Let’s imagine that a hacker has copied the Create Product page from MajorBank.com to Hackers.com – the hacker grabs the HTML source and places it at Hackers.com. Now, imagine that the hacker trick you into submitting the Create Product form from Hackers.com to MajorBank.com. You’ll get the following exception: The Cross-Site Request Forgery attack is blocked because the anti-forgery token included in the Create Product form at Hackers.com won’t match the anti-forgery token stored in the cookie in your browser. The tokens were generated at different times for different users so the attack fails. Preventing Cross-Site Request Forgery Attacks with a Single Page App In a Single Page App, you can’t prevent Cross-Site Request Forgery attacks using the same method as a server-side ASP.NET MVC app. In a Single Page App, HTML forms are not generated on the server. Instead, in a Single Page App, forms are loaded dynamically in the browser. Phil Haack has a blog post on this topic where he discusses passing the anti-forgery token in an Ajax header instead of a hidden form field. He also describes how you can create a custom anti-forgery token attribute to compare the token in the Ajax header and the token in the cookie. See: http://haacked.com/archive/2011/10/10/preventing-csrf-with-ajax.aspx Also, take a look at Johan’s update to Phil Haack’s original post: http://johan.driessen.se/posts/Updated-Anti-XSRF-Validation-for-ASP.NET-MVC-4-RC (Other server frameworks such as Rails and Django do something similar. For example, Rails uses an X-CSRF-Token to prevent CSRF attacks which you generate on the server – see http://excid3.com/blog/rails-tip-2-include-csrf-token-with-every-ajax-request/#.UTFtgDDkvL8 ). For example, if you are creating a Durandal app, then you can use the following razor view for your one and only server-side page: @{ Layout = null; } <!DOCTYPE html> <html> <head> <title>Index</title> </head> <body> @Html.AntiForgeryToken() <div id="applicationHost"> Loading app.... </div> @Scripts.Render("~/scripts/vendor") <script type="text/javascript" src="~/App/durandal/amd/require.js" data-main="/App/main"></script> </body> </html> Notice that this page includes a call to @Html.AntiForgeryToken() to generate the anti-forgery token. Then, whenever you make an Ajax request in the Durandal app, you can retrieve the anti-forgery token from the razor view and pass the token as a header: var csrfToken = $("input[name='__RequestVerificationToken']").val(); $.ajax({ headers: { __RequestVerificationToken: csrfToken }, type: "POST", dataType: "json", contentType: 'application/json; charset=utf-8', url: "/api/products", data: JSON.stringify({ name: "Milk", price: 2.33 }), statusCode: { 200: function () { alert("Success!"); } } }); Use the following code to create an action filter which you can use to match the header and cookie tokens: using System.Linq; using System.Net.Http; using System.Web.Helpers; using System.Web.Http.Controllers; namespace MvcApplication2.Infrastructure { public class ValidateAjaxAntiForgeryToken : System.Web.Http.AuthorizeAttribute { protected override bool IsAuthorized(HttpActionContext actionContext) { var headerToken = actionContext .Request .Headers .GetValues("__RequestVerificationToken") .FirstOrDefault(); ; var cookieToken = actionContext .Request .Headers .GetCookies() .Select(c => c[AntiForgeryConfig.CookieName]) .FirstOrDefault(); // check for missing cookie or header if (cookieToken == null || headerToken == null) { return false; } // ensure that the cookie matches the header try { AntiForgery.Validate(cookieToken.Value, headerToken); } catch { return false; } return base.IsAuthorized(actionContext); } } } Notice that the action filter derives from the base AuthorizeAttribute. The ValidateAjaxAntiForgeryToken only works when the user is authenticated and it will not work for anonymous requests. Add the action filter to your ASP.NET Web API controller actions like this: [ValidateAjaxAntiForgeryToken] public HttpResponseMessage PostProduct(Product productToCreate) { // add product to db return Request.CreateResponse(HttpStatusCode.OK); } After you complete these steps, it won’t be possible for a hacker to pretend to be you at Hackers.com and submit a form to MajorBank.com. The header token used in the Ajax request won’t travel to Hackers.com. This approach works, but I am not entirely happy with it. The one thing that I don’t like about this approach is that it creates a hard dependency on using razor. Your single page in your Single Page App must be generated from a server-side razor view. A better solution would be to generate the anti-forgery token in JavaScript. Unfortunately, until all browsers support a way to generate cryptographically strong random numbers – for example, by supporting the window.crypto.getRandomValues() method — there is no good way to generate anti-forgery tokens in JavaScript. So, at least right now, the best solution for generating the tokens is the server-side solution with the (regrettable) dependency on razor. Conclusion The goal of this blog entry was to explore some ways in which you need to handle security differently in the case of a Single Page App than in the case of a traditional server app. In particular, I focused on how to prevent Cross-Site Scripting and Cross-Site Request Forgery attacks in the case of a Single Page App. I want to emphasize that I am not suggesting that Single Page Apps are inherently less secure than server-side apps. Whatever type of web application you build – regardless of whether it is a Single Page App, an ASP.NET MVC app, an ASP.NET Web Forms app, or a Rails app – you must constantly guard against security vulnerabilities.

    Read the article

  • Codeigniter initializing multiple times per page load

    - by Clayton
    I'm using Codeigniter for my application and have something wrong with my configuration. When I load a page, the framework initializes several times (see logs below). I have built other applications with Codeigniter and have never seen this behavior before. Log output: DEBUG - 2010-03-27 14:50:32 --> Config Class Initialized DEBUG - 2010-03-27 14:50:32 --> Hooks Class Initialized DEBUG - 2010-03-27 14:50:32 --> URI Class Initialized DEBUG - 2010-03-27 14:50:32 --> Router Class Initialized DEBUG - 2010-03-27 14:50:32 --> Output Class Initialized DEBUG - 2010-03-27 14:50:32 --> Input Class Initialized DEBUG - 2010-03-27 14:50:32 --> XSS Filtering completed DEBUG - 2010-03-27 14:50:32 --> XSS Filtering completed DEBUG - 2010-03-27 14:50:32 --> XSS Filtering completed DEBUG - 2010-03-27 14:50:32 --> XSS Filtering completed DEBUG - 2010-03-27 14:50:32 --> Global POST and COOKIE data sanitized DEBUG - 2010-03-27 14:50:32 --> Language Class Initialized DEBUG - 2010-03-27 14:50:32 --> Loader Class Initialized DEBUG - 2010-03-27 14:50:32 --> Config file loaded: config/redux_auth.php DEBUG - 2010-03-27 14:50:32 --> Config file loaded: config/email.php DEBUG - 2010-03-27 14:50:32 --> Helper loaded: url_helper DEBUG - 2010-03-27 14:50:32 --> Helper loaded: form_helper DEBUG - 2010-03-27 14:50:32 --> Helper loaded: html_helper DEBUG - 2010-03-27 14:50:32 --> Database Driver Class Initialized DEBUG - 2010-03-27 14:50:32 --> Session Class Initialized DEBUG - 2010-03-27 14:50:32 --> Helper loaded: string_helper DEBUG - 2010-03-27 14:50:32 --> Helper loaded: file_helper DEBUG - 2010-03-27 14:50:32 --> Session routines successfully run DEBUG - 2010-03-27 14:50:32 --> Form Validation Class Initialized DEBUG - 2010-03-27 14:50:32 --> Model Class Initialized DEBUG - 2010-03-27 14:50:32 --> Controller Class Initialized DEBUG - 2010-03-27 14:50:32 --> Language file loaded: language/english/form_validation_lang.php DEBUG - 2010-03-27 14:50:32 --> XSS Filtering completed DEBUG - 2010-03-27 14:50:32 --> XSS Filtering completed DEBUG - 2010-03-27 14:50:32 --> Config Class Initialized DEBUG - 2010-03-27 14:50:32 --> Hooks Class Initialized DEBUG - 2010-03-27 14:50:32 --> URI Class Initialized DEBUG - 2010-03-27 14:50:32 --> Router Class Initialized DEBUG - 2010-03-27 14:50:32 --> Output Class Initialized DEBUG - 2010-03-27 14:50:32 --> Input Class Initialized DEBUG - 2010-03-27 14:50:32 --> XSS Filtering completed DEBUG - 2010-03-27 14:50:32 --> Global POST and COOKIE data sanitized DEBUG - 2010-03-27 14:50:32 --> Language Class Initialized DEBUG - 2010-03-27 14:50:32 --> Loader Class Initialized ... This repeats three more times

    Read the article

  • Do I only have to worry about XSS and Sql injection?

    - by Pranali Desai
    Hi All, I am writing an application and for this to make it safe I have decided to HtmlEncode and HtmlDecode the data to avoid Javascript Injection and Paramaterised queries to avoid Sql injection. But I want to know whether these are the best ways to avoid these attacks and what are the other ways to damage the application that I should take into consideration.

    Read the article

  • How can QA prevent defects?

    - by user970696
    Also according to Software Testing By Srinisvasan Desikan, Gopalaswamy Ramesh or ISTQB text books. Quality assurance is e.g. reviewing products, inspections, walkthroughs to see if all standards are being followed. This is preventive activity. I cannot see how this can be preventive? For the references: defect prevention (Quality Assurance) Software Testing By Srinisvasan Desikan, Gopalaswamy Ramesh Quality Assurance (QA) tries to go one step further. Instead of concentrating on post- facto defect detection and correction, it focusses on the prevention of defects from the very start. Managing Global Software Projects - Page 110 QA deals with prevention of defects in the product being developed. Software Testing and Quality Assurance

    Read the article

  • WMD Markdown and server-side

    Hello, I work since 2 days on WMD & Markdown and i don't find THE solution for stock data with security. I would like users can post html/xml (with WMD) on my site. For the moment, I stock data in Markdown format but If I disabled JavaScript the user can push easy XSS. If I strip_tags or html_entities all data i loose the user html/xml . How can I do ? In my opinion I must html_entities just the code between pre /pre, but how?! my data is in Markdown. After, how I can do for forbid xss attributes : <img src="javascript:alert('xss');" /> Sorry for my rusty english. MaxoU

    Read the article

  • Are SQL Injection vulnerabilities in a PHP application acceptable if mod_security is enabled?

    - by Austin Smith
    I've been asked to audit a PHP application. No framework, no router, no model. Pure PHP. Few shared functions. HTML, CSS, and JS all mixed together. I've discovered numerous places where SQL injection would be easily possible. There are other problems with the application (XSS vulnerabilities, rampant inline CSS, code copy-pasted everywhere) but this is the biggest. Sometimes they escape inputs, not using a prepared query or even mysql_real_escape_string(), mind you, but using addslashes(). Often, though, their queries look exactly like this (pasted from their code but with columns and variable names changed): $user = mysql_query("select * from profile where profile_id='".$_REQUEST["profile_id"]."'"); The developers in question claimed that they were unable to hack their application. I tried, and found mod_security to be enabled, resulting in HTTP 406 for some obvious SQL injection attacks. I believe there to be sophisticated workarounds for mod_security, but I don't have time to chase them down. They claim that this is a "conceptual" matter and not a "practical" one since the application can't easily be hacked. Their internal auditor agreed that there were problems, but emphasized the conceptual nature of the issues. They also use this conceptual/practical argument to defend against inline CSS and JS, absence of code organization, XSS vulnerabilities, and massive amounts of repetition. My client (rightly so, perhaps) just wants this to go away so they can launch their product. The site works. You can log in, do what you need to do, and things are visibly functional, if slow. SQL Injection would indeed be hard to do, given mod_security. Further, their talk of "conceptual vs. practical" is rhetorically brilliant, considering that my client doesn't understand web application security. I worry that they've succeeded in making me sound like an angry puritan. In many ways, this is a problem of politics, not technology, but I am at a loss. As a developer, I want to tell them to toss the whole project and start over with a new team, but I face a strong defense from the team that built it and a client who really needs to ship their product. Is my position here too harsh? Even if they fix the SQL Injection and XSS problems can I ever endorse the release of an unmaintainable tangle of spaghetti code?

    Read the article

  • Learning about security and finding exploits

    - by Jayraj
    First things first: I have absolutely no interest in learning how to crack systems for personal enrichment, hurting other people or doing anything remotely malicious. I understand the basis of many exploits (XSS, SQL injection, use after free etc.), though I've never performed any myself. I even have some idea about how to guard web applications from common exploits (like the aforementioned XSS and SQL injection) Reading this question about the Internet Explorer zero-day vulnerability from the Security SE piqued my curiosity and made me wonder: how did someone even find out about this exploit? What tools did they use? How did they know what to look for? I'm wary about visiting hacker dens online for fear of getting my own system infected (the Defcon stories make me paranoid). So what's a good, safe place to start learning?

    Read the article

  • Google propose un scanner open-source pour aider les développeurs webs à lutter contre les attaques

    Sécurité : Google propose un scanner open-source Pour aider les développeurs webs à lutter contre les attaques XSS et les injections de code Google vient de mettre à la disposition des développeurs webs un scanner open-source qui permet de tester les applications dès les premières étapes de leurs conceptions pour détecter d'éventuelles failles de sécurité. Baptisé Skipfish, l'outil offrirait, d'après les dires de son auteur, des fonctionnalités similaires à celles de Nmap ou Nessus. Il utilise la détection dite heuristique et permet de mettre à jour les vulnérabilités aux attaques de types cross-scritping (XSS) et aux injections SDQ et XML, entre autres failles.

    Read the article

  • HTML Purifier: Removing an element conditionally based on its attributes

    - by pinkgothic
    As per the HTML Purifier smoketest, 'malformed' URIs are occasionally discarded to leave behind an attribute-less anchor tag, e.g. <a href="javascript:document.location='http://www.google.com/'">XSS</a> becomes <a>XSS</a> ...as well as occasionally being stripped down to the protocol, e.g. <a href="http://1113982867/">XSS</a> becomes <a href="http:/">XSS</a> While that's unproblematic, per se, it's a bit ugly. Instead of trying to strip these out with regular expressions, I was hoping to use HTML Purifier's own library capabilities / injectors / plug-ins / whathaveyou. Point of reference: Handling attributes Conditionally removing an attribute in HTMLPurifier is easy. Here the library offers the class HTMLPurifier_AttrTransform with the method confiscateAttr(). While I don't personally use the functionality of confiscateAttr(), I do use an HTMLPurifier_AttrTransform as per this thread to add target="_blank" to all anchors. // more configuration stuff up here $htmlDef = $htmlPurifierConfiguration->getHTMLDefinition(true); $anchor = $htmlDef->addBlankElement('a'); $anchor->attr_transform_post[] = new HTMLPurifier_AttrTransform_Target(); // purify down here HTMLPurifier_AttrTransform_Target is a very simple class, of course. class HTMLPurifier_AttrTransform_Target extends HTMLPurifier_AttrTransform { public function transform($attr, $config, $context) { // I could call $this->confiscateAttr() here to throw away an // undesired attribute $attr['target'] = '_blank'; return $attr; } } That part works like a charm, naturally. Handling elements Perhaps I'm not squinting hard enough at HTMLPurifier_TagTransform, or am looking in the wrong place(s), or generally amn't understanding it, but I can't seem to figure out a way to conditionally remove elements. Say, something to the effect of: // more configuration stuff up here $htmlDef = $htmlPurifierConfiguration->getHTMLDefinition(true); $anchor = $htmlDef->addElementHandler('a'); $anchor->elem_transform_post[] = new HTMLPurifier_ElementTransform_Cull(); // add target as per 'point of reference' here // purify down here With the Cull class extending something that has a confiscateElement() ability, or comparable, wherein I could check for a missing href attribute or a href attribute with the content http:/. HTMLPurifier_Filter I understand I could create a filter, but the examples (Youtube.php and ExtractStyleBlocks.php) suggest I'd be using regular expressions in that, which I'd really rather avoid, if it is at all possible. I'm hoping for an onboard or quasi-onboard solution that makes use of HTML Purifier's excellent parsing capabilities. Returning null in a child-class of HTMLPurifier_AttrTransform unfortunately doesn't cut it. Anyone have any smart ideas, or am I stuck with regexes? :)

    Read the article

  • New January 2013 Release of the Ajax Control Toolkit

    - by Stephen.Walther
    I am super excited to announce the January 2013 release of the Ajax Control Toolkit! I have one word to describe this release and that word is “Charts” – we’ve added lots of great new chart controls to the Ajax Control Toolkit. You can download the new release directly from http://AjaxControlToolkit.CodePlex.com – or, just fire the following command from the Visual Studio Library Package Manager Console Window (NuGet): Install-Package AjaxControlToolkit You also can view the new chart controls by visiting the “live” Ajax Control Toolkit Sample Site. 5 New Ajax Control Toolkit Chart Controls The Ajax Control Toolkit contains five new chart controls: the AreaChart, BarChart, BubbleChart, LineChart, and PieChart controls. Here is a sample of each of the controls: AreaChart: BarChart: BubbleChart: LineChart: PieChart: We realize that people love to customize the appearance of their charts so all of the chart controls include properties such as color properties. The chart controls render the chart on the browser using SVG. The chart controls are compatible with any browser which supports SVG including Internet Explorer 9 and new and recent versions of Google Chrome, Mozilla Firefox, and Apple Safari. (If you attempt to display a chart on a browser which does not support SVG then you won’t get an error – you just won’t get anything). Updates to the HTML Sanitizer If you are using the HtmlEditorExtender on a public-facing website then it is really important that you enable the HTML Sanitizer to prevent Cross-Site Scripting (XSS) attacks. The HtmlEditorExtender uses the HTML Sanitizer by default. The HTML Sanitizer strips out any suspicious content (like JavaScript code and CSS expressions) from the HTML submitted with the HtmlEditorExtender. We followed the recommendations of OWASP and ha.ckers.org to identify suspicious content. We updated the HTML Sanitizer with this release to protect against new types of XSS attacks. The HTML Sanitizer now has over 220 unit tests. The Ajax Control Toolkit team would like to thank Gil Cohen who helped us identify and block additional XSS attacks. Change in Ajax Control Toolkit Version Format We ran out of numbers. The Ajax Control Toolkit was first released way back in 2006. In previous releases, the version of the Ajax Control Toolkit followed the format: Release Year + Date. So, the previous release was 60919 where 6 represented the 6th release year and 0919 represent September 19. Unfortunately, the AssembyVersion attribute uses a UInt16 data type which has a maximum size of 65,534. The number 70123 is bigger than 65,534 so we had to change our version format with this release. Fortunately, the AssemblyVersion attribute actually accepts four UInt16 numbers so we used another one. This release of the Ajax Control Toolkit is officially version 7.0123. This new version format should work for another 65,000 years. And yes, I realize that 7.0123 is less than 60,919, but we ran out of numbers. Summary I hope that you find the chart controls included with this latest release of the Ajax Control Toolkit useful. Let me know if you use them in applications that you build. And, let me know if you run into any issues using the new chart controls. Next month, back to improving the File Upload control – more exciting stuff.

    Read the article

< Previous Page | 6 7 8 9 10 11 12 13 14 15 16 17  | Next Page >