Cross-Site Scripting: An attack method that involves injection of code or markup into a webpage. There are three major types of XSS: Reflected XSS, Stored XSS (aka persistent XSS), DOM-based XSS (aka client side XSS).

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What is the danger of Reflected Cross Site Scripting?

What is the danger of Reflected Cross Site Scripting? I understand the Reflected XSS is dangerous, because it's possible. But what practical attacks can be performed using Reflected XSS?
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scanning my site for JavaScript/XSS vulnerabilities [closed]

It have had a report that my site may have a security issue and there is some JavaScript loading 10 times per second. www.ayrshireminis.com Is there anyway that I can "scan" my site to check if ...
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Why ban XSS instead of flagging it?

Consider a browser that allows an XMLHttpRequest downloaded from foo.net to make requests to bar.net, but attaches a XHR-Origin: http://foo.net (or possibly a more descriptive value like ...
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Web Application Firewall Rule Optimization

Following are the two Rules taken from ModSecurity CRS core Ruleset. These two rules are base Rules for XSS attacks. If we look at these two rules their variables and actions are same what they differ ...
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What is cross-site-scripting? [duplicate]

Possible Duplicate: Can anybody explain XSS to an idiot? First I ask is there an aboslute definition? I've done some Googleing and it seems like everyone says something different. On SO ...
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Can anybody recommend any gems for checking security vulnerabilities?

I want to check one of my RoR projects for security vulnerabilities. So can anybody recommend any gems for my needs?
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HTTP TRACE vulnerability discovered - what should I do

First, why is HTTP TRACE method allowed on a website Isn't it a bad thing for web server or its users' security? Second, when I run the following PHP script via my browser... <?php $service_port ...
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Risks of serving untrusted content under HTTP Content-Type: text/plain?

Am I gonna run into XSS attacks by doing this, or will a file download be prompted? Are there security problems that would rise in a modern browser?
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Are sandboxes overrated?

I've stumbled upon the following on the blog of the NoScript developer Giorgio Maone. First, he quotes the following ArsTechnica article about an XSS bug in Adobe Flash: As useful as sandboxes ...
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Does Google Chrome protect against cross site scripting (XSS)?

In Firefox I've been using the NoScript extension to protect myself from certain kinds of malware attacks. NoScript is well known as a very powerful extension for Firefox and introduced protection ...
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Why doesn't the same origin policy block get requests what contain arguments?

From what I understand, the same origin policy prevents scripts in a web page from talking to servers outside of the present domain (using post, xmlhttprequest, etc). I assumed that get requests ...
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Is it possible to forge post request and bypass maxlength in input box?

I have input box with maxlength=12, and that input box is vulnerable to xss. But because of maxlength 12 it is not possible to construct any really valid xss vector. The user input is stored in the ...
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Does setting the cookie-path protect me from XSS from another context?

Lets say I am using a reverse proxy with URL rewriting that provides access to 2 different applications http://www.example.com/app1/ and http://www.example.com/app2/. I don't want those ...
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594 views

LFI or RFI from XSS?

Could XSS lead us to the Local File Include or Remote File Include? I read article that it's possible to upload shell via XSS vulnerability, but I still have no idea how it had been achieved.
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Multibyte Character Exploits JSP/PostgreSQL

I am trying to secure a web application, written in Java/JSP and running on PostgreSQL, against SQL injection. I ran into this very interesting answer, which refers to PHP and MySQL. Is there any ...
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sanitizing likes/unlikes in application?

I've got a function in my app where users can click on a "thumbs up" image and a like is recorded in the database; all that's recorded is the user's ID and the ID of the post that the user liked. I ...
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Where is cross-site scripting code processed?

Where does the snippet or Javascript get processed when we enter that in input box of HTML page or any URL? Does it go to the server and come back or does the browser process it?
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Is it a security risk to embed a commenting service (like Disqus) into our site?

Can commenting services like Disqus, IntenseDebate, etc. pose a security risk for corporations? Edit: What risks could arise when embedding such services into corporate websites?
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Is it possible to inject HTML into image to provoke XSS?

Some answers mention that it's possible to inject attacker-controlled HTML into images and therefore provoke XSS. I guess that this HTML will be processed by browser only if hole exists in browser. ...
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How to fix specific XSS issues in URL via php?

I am using Netsparker community edition for checking my app for any general security holes. I'm getting a lot of following XSS probable issue areas: my_php_file.php?nsextt=" ...
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header injection + codeigniter

I'm reading through Mozilla's Secure Coding Guidelines, and found this statement: Don't trust any user data (input, headers, cookies etc). Validate it before using it I'm using the codeigniter ...
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javascript:alert(“test”); command does not work

Hello! As I have done before and also have read in many web sites, that just simply writing: javascript:alert(document.cookie); should work on any web page. But now, I was not able to execute it. I ...
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How can I execute a XSS with these conditions?

I am trying to learn penetration testing and I have downloaded a vulnerable application called "Bodgeit Store". I have finished almost all the challenges except one which is to execute a Cross-Site ...
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How do I use Markdown securely?

How do I use the Markdown library safely? What do I need to do to make sure that its output is safe to include into my web page? I want to allow untrusted users to enter content (in Markdown ...
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Is it Illegal to break out of a forum post by using CSS for example?

Is it illegal in the UK to post styling that breaks out of a post? For instance, if styling were allowed here and I were to use it to change some stackexchange pictures on this page, would that be ...
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Best Approach for removing XSS Vulnerability

I have been developing a Webobjects application, and I found that my application is vulnerable to XSS through URL, but not when malicious input like <script>alert("hi")</script> is input ...
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XSS : Content-type: application/json

Background information - Application responds to request to a particular URL with content-type: application/json JSON response contains a parameter from the request Escapes the quote with a slash ...
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Security issues using iframes

We are looking to move to iframes due to technical challenges. By moving to iframes it will be easier to manage the technical issues. But we are not totally sure of security implications of iframes. ...
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Is e-mail a direct vector for XSS

I'm curious if there is a way to execute XSS via email. I am not talking about using e-mail as a way to deliver a link that has reflected XSS in it. I'm talking about sending an email from ...
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Interpolique: transparently preventing SQL Injection and XSS with base64 encoding, what happened?

For the keynote at The Next HOPE a couple of years ago, Dan Kaminsky unveiled Interpolique (the talk is really fun btw). The problem he raised was how to defend against injection attacks, including ...
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For untrusted user upload sites: what should the contents of crossdomain.xml and clientaccesspolicy.xml be?

Flash has a long history of ignoring MIME types of files and reading the file directly for executable content or for cross domain execution permissions. That means a malicious user can take advantage ...
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Will JavaScript be executed which is in an HREF?

I located an issue with a site where I can insert a script tag into the href of an anchor tag: <a href="<script>alert(8007)</script>">Click Me</a> What I am trying to ...
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Notable XSS attacks in 2011

I am wondering what notable events in XSS attacks we saw in 2011. What big events hit the infosec community in regards of XSS? I am thinking of specific events like for example the Samy worm in 2007 ...
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How do I figure out how malware infected my server, and the subsequent sites on the server?

I recently was in charge of fixing our server at work, and cleaning the sites on it. We were infected with some malware that injected some code into some of our clients websites. Apparently, there was ...
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Removing Google Analytics cookie string from URL - security hole?

On our site, we use google analytics and we have to put the GA cookie in the URL since we have a two letter domain and IE imposes some cookie limitations on those. This means that when going between ...
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How much security should I use for my web application?

My question is, for a "normal" site, what do you think is enough to secure against methods used by "script kiddies"? For example, SQL injection, XSS, and stuff like that. Same question for password ...
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Is this JSON encoding vulnerable to CDATA injection?

I ran across an odd notation in the jsfiddle.net generated pages <script type='text/javascript'>//<![CDATA[ $(window).load(function(){ $('form, table').animate({ opacity: 1 }); ...
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Bypassing XSS filters [duplicate]

Possible Duplicate: New XSS cheatsheet? Can anyone give me list of ways to encode XSS payload , or to be precise what are the ways to encode XSS payload to bypass encoding of <> or (). I ...
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Is this jQuery ajax call vulnerable to XSS?

If somebody can edit $("#field").val(), can they change the url property here to point to another location? $.ajax({ url: "http://mywebsite/script?param=" + $("#field").val(), dataType: "jsonp", ...
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Is XSS dangerous on web without login/sensitive user's data?

Is XSS dangerous when the web application doesn't have a login/register function, the user isn't logged in or when the website doesn't store any sensitive user information?
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Is strip_tags() horribly unsafe?

I always use strip_tags to prevent XSS attacks, but today I saw a post which was telling it's horribly unsafe. As the manual says, it doesn't check for malformed HTML! Is it true? What can I do to ...
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How bad is a Self Contained XSS attack?

Some of you might be familiar with this attack called Self Contained XSS. I recently stumbled upon this article about it. So how bad this kind of attack can be, even though this doesn't have access to ...
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Presentation on Web App Security (ACM Student Chapter)

I am a member of the local ACM student chapter in my university and as part of our activities I am scheduled to give a talk on current issues on Web Application Security (and possibly secure coding ...
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Is Request.getHeader(“host”) vulnerable?

If the following is the code snippet, what would be your suggestions? <script type="text/javascript" src="<%=request.getHeader("Host")%>/XXX/xxx.js"></script> Is this a clear ...
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XSS in SWF file

I have the following code in an SWF file that a vulnerability scanner marks as XSS: // Action0 { var __callResult_6 = getURL(_root.thankYou, "_self"); var __callResult_7 = stop(); ...
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Filter user input before the database or upon display?

Given a web application where user data must be properly escaped to avoid XSS, is it better to try to remove the "bad stuff" before it enters the database, or is it best to allow it in the database ...
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Is there a way to bypass escape function in javascript?

Is there a way to bypass escape function in javascript for exploiting a XSS vulnerability ?
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DOM XSS : Need Help

I was trying my hands at DOM based XSS. I came across a scenario where user controlled string from the URL is included in javascript as below var userControlled=substring of URL; ...
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Closing an HTML element without using literal slashes?

I'm investigating a vulnerability in an application that echoes a user-supplied filename without sanitizing the filename. E.g. a file named test-<script>alert("evil");.txt will result in that ...
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Server wide javascript injection

UPDATE: The server was rooted, php.ini was replaced that cause the injection to appear. Still haven't figured out which directive is injecting the javascript. I'm troubleshooting a hacked website ...