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) and DOM-based XSS (aka client side XSS).

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Escaping rich text editor output

When having a rich text editor on a web application, what is the best way to escape HTML entities and prevent XSS attacks but keep the formatting (<b>, <i>, <u>, ...etc.) ?
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Would using Google reCAPTCHA allow Google to cheat?

Wanting to go a step further into reducing the attacking surface from my "register new user" form I think on using reCAPTCHA (the one Google offers). Having bots sorted out from being able to ...
7
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2answers
835 views

How does BeEF work and how can it be persistent

BeEF - the browser exploitation framework. I think (thought) I had a basic working understanding of how it works. Recently, though, I was watching, this DEFCON talk, where a hacker used a ...
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2answers
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Is it safe to use createHTMLDocument to sanitize HTML?

i'm wondering how safe it is to use createHTMLDocument to do HTML sanitization. I've tried to implement it like this: function sanitize(string) { var elm = ...
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4answers
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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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1answer
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Notable XSS attacks in 2011 [closed]

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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2answers
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If using htmlentities or htmlspecialchars functions is enough for block XSS attack

I know this question was discussed on net various times. and people give some example how to bypass these functions through passing some code. But here one issue, All example of ...
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2answers
5k views

How to address XSS security issues in FCKeditor / CKeditor?

A security report we conducted through an outside company reported XSS vulnerabilities in FCKeditor which we're using in our PHP application. They pointed out that accessing URLs such as: ...
5
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3answers
112 views

Input validation: how to do it if I must accept HTML as part of my input?

I'm writing a service which receives FHIR data and it stores it. FHIR is an HL7 healthcare information standard format which contains HTML by definition, embedded into a JSON or XML, (to ensure ...
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2k views

Are phone apps vulnerable to XSS or CSRF? (Webview, Phonegap, chrometab)

I need to provide evidence that CSRF or XSS is possible on a phone... using PhoneGap, a Webview, or specifically a "Chrome Tab" or iOS equivalent. I believe in theory this is possible, and mitigation ...
4
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3answers
238 views

Why doesn't XSS vulnerability from the site launching the CSRF attack make the Synchronizer Token Pattern insecure?

I was reading this question about using Synchronizer Token Pattern to protect against CSRF and the comments of the answer intrigued me. Of course, as the last comment says, if your site has an XSS ...
4
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2answers
505 views

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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3answers
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Altering a $_SESSION variable in PHP via XSS?

Not sure if what I'm saying makes sense... but is it possible for me to alter a $_SESSION variable from outside the target PHP script? One of our scripts uses a $_SESSION variable and I'm not sure if ...
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2answers
206 views

Classifying Reflected and DOM-based XSS

Having referenced Difference between DOM & Reflected XSS , I observed that certain attacks could be both DOM-based and Reflected XSS. I wish to find out if my understand is accurate, or they ...
2
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1answer
163 views

Reflected XSS via $_FILES

Is it possible to perform a reflected XSS attack via the $_FILES variable? The vulnerable code I am imagining might look like this: echo $_FILES["file"]["name"]; I read that it's not possible to ...
2
votes
3answers
123 views

Temporary XSS Vulnerability

I found xss on a textarea field. When you enter a character to this field it output the character in real time so when I input the following code: <input onclick=alert(document.cookie)> there ...
2
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2answers
507 views

Stealing document.cookie from Google domain, is this a privacy breach?

When I am logged into the Google and prints document.cookie I could see following cookies. My doubt is what all an attacker can do if attacker could steal these cookies of the victim using exploiting ...
2
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1answer
3k views

Uploading images safe of XSS, php code and virus

I know that my question has been responded lot of times, but most the responses addresses functions that I don't even use (like use include with images) and that makes me worry because maybe I'm not ...
2
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4answers
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Current best practices to prevent persistent XSS attacks

I have a text field that allows the user to type whatever he/she wants. After saving, the results are later displayed on the screen to potentially many people. XSS seems a bit like black magic to ...
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1answer
387 views

Is this enough to tackle script / malicious code insertion in GET, POST requests?

I've got legacy PHP code which attempts to prevent script/SQL injection with the following: if (!empty($_POST)) { reset($_POST); while (list($k,$v)=each($_POST)) { ...
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1answer
666 views

Is addslashes + htmlentities sufficiently secure?

I have addslashes(htmlentities($userInput)). It gets inserted into my database. (NOT a mysql db) Is it sufficiently safe from xss? Thank you!
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3answers
904 views

Any eventhandlers that apply to hidden elements?

I'm trying to XSS a search field and my attack vector is getting reflected like this: <input type="text" id="txtRpHiddenKeyword" style="display: none;" value="ATTACK VECTOR HERE" /> Only ...
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1answer
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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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2answers
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DOM XSS attack failing in Firefox

I am trying to perform DOM XSS attack to exploit a vulnerability of localhost webpage. I am able to perform the attack successfully on IE-11 and Chrome. But Firefox is preventing me to perform the ...
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2answers
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JavaScript eval() to parse JSON after sanitizing with regexes — is XSS possible?

Is possible to bypass my regex and execute any JavaScript? <script> function json(a){ if (/^\s*$/.test(a) ? 0 : /^[\],:{}\s\u2028\u2029]*$/.test(a.replace(/\\["\\\/bfnrtu]/g, ...
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1answer
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Cannot turn off XSS filter in Chrome

I am using the following command to launch Chrome: "C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --args --disable-web-security to turn off XSS auditor in chrome in Windows 7, but ...
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3answers
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Stored Cross-Site Scripting Without Parentheses or Spaces

I'm testing a commenting application that takes a link of the form http://google.com and puts it in an href tag as so: <a rel="nofollow" href="http://google.com"> The resulting comment is ...
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2answers
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Minimum size of input text box required for XSS attacks

I have below code to accept User login ID as input from User. <input name="userName" type="text" id="userID" maxlength="8"/></td> Maximum number of characters that a end user can input ...
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2answers
1k views

Is Drupal's filter_xss enough for filtering HTML?

Drupal has filter_xss function. Is it safe to use for filtering arbitrary user HTML input? If not, what should be used instead when using Drupal 7? This questuion is a duplicate of Drupal's built-in ...
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2answers
2k views

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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1answer
490 views

Preventing reflected XSS in URL [duplicate]

We have just had some pen testing completed against a web application and the one area identified as High Impact and Medium Probability was: Cross-Site scripting (reflected) The example given was ...
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2answers
527 views

XSS via REQUEST_URI

Is there any situation where an XSS attack can be performed via the PHP $_SERVER['REQUEST_URI'] variable? For those unfamiliar with it: It contains the complete URL used to access that website, ...
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2answers
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Reflective XSS in script codes with Content Type “text/javascript”

I have a webpage that returns raw script code with the headerContent-Type: text/javascript. However I found that there is a reflective xss in one of the parameters passed to the url which is copied ...