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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4answers
2k views

Does default ModSecurity protect enough against XSS?

It's been a few years since I mucked around with modsecurity... Will simply installing the package with the default rules provide enough validation to prevent any (okay, let's be honest - best we ...
14
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4answers
954 views

Web Security Cheatsheet / ToDo list

Can anyone suggest a cheatsheet or ToDo list of web site and application security? A local small business owner prompted a question about web security, basically her company website just got XSS ...
5
votes
3answers
359 views

Is Content Security Policy an approach that is worth to support?

Mozilla Firefox 4.0 supports something called Content Security Policy that disables the interpretation of embedded Java Script. Only external Java Script files that are referenced using a script tag ...
1
vote
2answers
405 views

AntiXSS for ASP.NET 1.1

Unfortunately, a client of mine still has an application based on ASP.NET 1.1. Yes yes, I know - horribly insecure, support ending, and on and on... I've already been through that with them. ...
0
votes
4answers
138 views

Safely changing text links to HTML anchors

I'm trying to change text links to real anchors. So for example I want to change http://example.com to <a href="http://example.com">http://example.com</a>. Since this is a user given ...
4
votes
3answers
5k views

Testing PHP form injection

I'm writing a very small PHP app that takes input via a form. As could be expected for a first revision, the code does no escaping or sanitisation of input: if( $_POST["var"] != "" ) { print ...
1
vote
1answer
322 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)) { ...
3
votes
3answers
1k views

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 ...
1
vote
1answer
182 views

Replicating javascript actions from different website (XSS?)

I've got html / javascript code on my site like this: <a ...
3
votes
2answers
314 views

Protecting websites from outdated browsers and plugins via a whitelist/blacklist combination?

Aside from using browser headers, I want to blacklist/whitelist browser and plugins from my site so that I can prevent these older unpatched systems from (1) being a general user of my site (2) ...
10
votes
2answers
3k 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: ...
58
votes
6answers
6k views

Can anybody explain XSS?

I work programming Enterprise Java applications and do very little web development in 2002. I'm interested in security and like to read articles about it. However, I never fully understand how XSS ...
7
votes
4answers
1k views

Escaping JavaScript constants

how can untrusted values be included in a html-page as javascript string constants? Although the case i am asking uses JSF and Rails, I think this is a general problem independent of the server side ...
10
votes
7answers
1k views

Whitelisting DOM elements to defeat XSS

As we know, developers are responsible for correctly escaping/validating data provided by the user before rendering or storing them. However, we must agree that it's relatively easy to forget a single ...
38
votes
5answers
3k views

New XSS cheatsheet?

There is a great list of XSS vectors avaliable here: http://ha.ckers.org/xss.html, but It hasn't changed much lately (eg. latest FF version mentioned is 2.0). Is there any other list as good as this, ...
23
votes
6answers
356 views

User input data, is filtering enough or should it be parsed?

In a webapplication there could be two approaches to migate XSS attacks. All the input data could be filtered (removing all 'bad' data), or the input could be parsed, tokenized and output with only ...
16
votes
3answers
939 views

Rails - protection against code injection and XSS

I've started using Ruby on Rails, and I was wondering if there were any security gotchas to watch out for with Rails, particularly regarding code injection and XSS? I know Rails tries to prevent ...