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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Is Django's built-in security enough?

I have learned that Django provides built-in protection against the three main types of web app attacks (SQL injection, XSS and CSRF), which is really awesome. Yet I have spoken to a few Django ...
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285 views

Email Compromised due to Yahoo Mail Exploit

On Monday due to XSS vulnerability present in the Yahoo mail my email has been compromised. I have immediately changed my password but i am not sure is this enough i.e. do i need to delete my cookies ...
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223 views

Question about XSS example

A friend of mine received an email from someone (a reputable sender), and I noticed that the following was tagged onto the end of the subject: ...
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673 views

Closing an HTML tag without using the actual character

I'm currently learning how to perform XSS on websites, but there is a constant problem that keeps recurring that I'm sure must be easy to bypass. Quite often, the website will filter out quotation ...
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3answers
879 views

What does a HTML filter need to do, to protect against SVG attacks?

I recently learned that SVG (Scalable Vector Graphics) images introduce a number of opportunities for subtle attacks on the web. (See paper below.) While SVG images may look like an image, the file ...
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3answers
787 views

How can this xss challenge be solved? [closed]

I found this : http://research.insecurelabs.org/xssmas/ And so far my solutions were: 1.http://research.insecurelabs.org/xssmas/search.php?query=<script>alert(0)</script> 2. ...
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What does scorecardsresearch.com/beacon.js - added by Disqus.com - do?

I recently added Disqus to my site. Looking at the "scripts" tab on Firebug, I noticed a script called, http://scorecardresearch.com/beacon.js (here is a prettified version - the script is not ...
3
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1answer
287 views

How did the Tumblr worm spread?

Recently Tumblr was hit by a fast-spreading worm. How did the worm work? What was the vulnerability in Tumblr that it exploired? Did it exploit a XSS vulnerability in Tumblr? A CSRF vulnerability ...
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351 views

Need an explanation of Cross-Site Flashing?

I found this - can anyone provide me examples of how these issues are exploited?
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1answer
269 views

Possible to execute a non-persistent XSS attack without using the url/query string?

I've been reading up on non-persistent XSS and all of the examples I have found use the situation where a webpage takes something from the url/query string and places it on the page. Is there any ...
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Is it possible to make an xss with only html tags

I'm not aware of all the xss tricks.. While programming in Ruby on Rails, using a sanitize method to allow only certain tags and it makes its best to clear all the other tags and scripts the ...
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I need explanation on how serious these vulnerabilities are?

I have found two vulnerabilities on my college site and I want to report them but don't know if these are "really" vulnerabilities : RFI inside SWF file. Example: ...
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referrer checking as a defence for XSS attack

After reading the question about referrer and the answer of @D.W., I did not understand the following part: XSS defense. Strict referer checking can make reflective XSS attacks harder, because ...
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4answers
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What XSS attacks doesn't “Reflective XSS Protection” defeat?

Its been quite a while since I have played with cross site scripting vulnerabilities but today I came across a website today that was crying out to be tested for a basic XSS vulnerability. So ...
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1k views

Drupal filters XSS with regexes. What could bypass it?

Drupal filters HTML strings against XSS attacks using regexes: http://api.drupal.org/api/drupal/includes%21common.inc/function/filter_xss/7 However, as a lot of people know, HTML can't be parsed with ...
0
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1answer
1k views

How to escape user input in a value of javascript object?

How to properly escape user-controlled input when it's inserted as a value in JSON object? <script> $(document).ready(function() { new MyObject({ key1: "user_input", key2: ...
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873 views

How to show xss alert box when you are inside function in <script> tag?

For example we have this: <script type="text/javascript" charset="utf-8"> $(function () { var stranica = "#aXSSinjection point"; var stranicaContainers = $('div.stabs > ...
4
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2answers
329 views

filtering content in Content disposition header

I was reading "The Tangled Web"(A book that I'm enjoying very much) and I have a doubt in the following excerpt taken from it :- When Handling User-Controlled Filenames in Content-Disposition Headers ...
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710 views

CSRF Protection on static pages

I have a static site which has forms. The forms submit to a Rails endpoint which captures the submitted data. The static site and the Rails endpoint are on the same domain, on different subdomains and ...
8
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363 views

E-mail read receipt through XSS

I recently stumbled upon a really silly/unsafe but an interesting way to get a read receipt of an e-mail. I'm not 100% sure if the method in use works, which is why I'm asking it here. G-mail does ...
3
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5answers
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Efficient way for finding XSS vulnerabilities?

Manual (reliable) way: Put string containing characters that have special meaning in HTML into some parameter of HTTP request, look for this string in HTTP response (and possibly) in other places ...
5
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2answers
4k views

How can I prevent reflected XSS in my JSON web services?

I have a web service that takes POST data (JSON) and returns part of the request object in the JSON response. This is open to XSS if the response is rendered as HTML by the browser since someone ...
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5answers
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XSS : Blacklist characters vs. whitelist

I have been studying to prevent my web app against XSS. I read about it on OWASP and other security channels, they all say that use ESAPI and similar library, and also do input filtering through ...
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2answers
990 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 ...
5
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1answer
2k views

XSS inside CSS when " is encoded?

I'm trying to make XSS work on one site.It allows me to edit CSS which is then included inside web page source , but it won't allow me to use " , only ' . Source is like this: body { margin: 0; ...
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1answer
270 views

Where does the responsibility lie for a XSS vulnerability

I am an avid user of Workflowy (online outliner/note taking tool) and I installed the Chrome extension 'Workflowy for Coders', which formats the text within notes. I discovered that one of my notes ...
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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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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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1answer
711 views

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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207 views

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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270 views

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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2answers
420 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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378 views

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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686 views

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 that 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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2answers
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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 ...
3
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625 views

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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887 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.
3
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281 views

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 ...
2
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3answers
436 views

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 ...
0
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2answers
152 views

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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764 views

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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3answers
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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. ...
2
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3answers
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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 ...