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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136 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 ...
2
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3answers
897 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 ...
0
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2answers
157 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
82 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
236 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 ...
0
votes
1answer
327 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 ...
41
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3answers
3k views

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
votes
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 ...
0
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2answers
365 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 ...
9
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3answers
347 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
votes
2answers
267 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 ...
8
votes
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
votes
1answer
212 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 ...
6
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2answers
498 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, ...
2
votes
1answer
951 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 ...
5
votes
2answers
463 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
votes
3answers
247 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 ...
1
vote
4answers
739 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
votes
1answer
468 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
votes
1answer
688 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
votes
2answers
1k 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
votes
2answers
286 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?
2
votes
1answer
258 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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votes
1answer
477 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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votes
1answer
116 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
123 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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votes
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 ...
2
votes
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
votes
2answers
792 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 ...
13
votes
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
votes
2answers
365 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 ...
23
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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, ...
3
votes
6answers
1k views

Is cookie-based XSS exploitable?

Today I've found interesting site that output your cookie value directly to the page, so if I modify the cookie value I can XSS myself. e.g <span id=statistics>Last visit: ...
2
votes
2answers
137 views

Is it safer to store the XSRF value inside your JavaScript?

To protect yourself against XSRF, you need to have a separate token on a page. See: Coding Horror: Preventing CSRF and XSRF Attacks, by Jeff Atwood As the posting suggests, its best to have those ...
10
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5answers
1k views

CSRF protection with Session Id

To protect against CSRF, couldn't my page javascript just dynamically insert the session id from the cookie into the body of each HTTP request right before it's sent? The server would then just ...
8
votes
2answers
839 views

Type 2 XSS vs CSRF

Trying to create a thorough understanding of XSS and CSRF, i'm clear that a type 2 xss involves an exploit that is persistent on the server. e.g. <SCRIPT type="text/javascript"> new ...
4
votes
2answers
600 views

XSS: Parsing Javascript

Reading about DOM based XSS from http://www.webappsec.org/projects/articles/071105.shtml It illustrates some examples like: ...
3
votes
1answer
627 views

XSS via Unicode

Reading about XSS and its countermeasures from http://www.xssed.com/xssinfo#Avoiding_XSS_vulnerabilities , it says (in the 2nd last paragraph of the link) that: […] support for Unicode character ...
0
votes
1answer
2k views

Security Testing AngularJS Web Application

An angularjs application stores user input to local/sessionStorage and retrieves it later to fill the form fields or display that content later. If a javascript is submitted as user input, it gets ...
11
votes
3answers
554 views

Is stripping out < and > characters an effective way of preventing XSS?

I'm guessing that HTML encoding the input would probably be a better solution, but I'm curious if just stripping out any < and > characters would be an effective defense against XSS attacks. ...
0
votes
1answer
150 views

Dom xss posibility question?

I have this snippet of code : <script type="text/javascript"> $.extend({ getUrlVars : function() { var vars = [], hash; ...
3
votes
4answers
2k views

how can you inject malicious code into an innocent-looking URL?

I am learning about XSS attacks. Wikipedia says that in a non-persistent attack an attacker may provide an innocent-looking URL that "points to a trusted site but actually has an XSS vector." What ...
1
vote
1answer
75 views

Benefits of Content Security Policy

I would like to know how really good is the content security policy header for preventing XSS considering the following : Many sites have inline JS / CSS. The request/ response headers can be ...
3
votes
1answer
147 views

What are good tools for CRLF discovery? [closed]

What are good tools for finding CRLF injection vulnerabilities?
7
votes
3answers
2k views

Is there a way to bypass Django's XSS escaping with “unicode”?

Django (the Python web framework) escapes output to prevent XSS (Cross Site Scripting) attacks. It replaces ', ", <, >, & with their HTML safe versions. However this presentation on slide ...
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vote
1answer
276 views

XSS MySQL Database Accessible?

I'd like to know if there is any danger of someone being able to access the database via XSS vulnerabilities on this page. I have the following link. When you go to this link, the text I've enclosed ...
1
vote
1answer
949 views

bypass a regex filtration to perform an xss attack

Does the regex [\w/$!.*-]+$ stop the injection of payloads like : "><script>alert(4)</script> " onload="alert(4)" ...
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votes
1answer
282 views

can someone break my anti dom based xss from the window location? [closed]

can someone break my anti dom based xss from the window location ? function parseparameters() { var href = window.location.href; var id = href.indexOf('#'); if (id ...
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votes
1answer
231 views

some questions about DOM based XSS [closed]

Is it possible to do a DOM based xss attack with window.location.protocol? How can we use dom based xss with document.title? How can we bypass the escape javascript function if it is used? thank ...
0
votes
1answer
571 views

Sanitizing JavaScript to prevent XSS

I'm going through a vulnerability remediation exercise for a client and am trying to figure out how to best mitigate this particular hole. There's a script on our site that calls up content into a new ...