Tagged Questions

-3
votes
0answers
23 views

How to use FCKeditor safely ? [duplicate]

How can I implement FCKeditor in my website keeping it secure from Cross Site Scripting. I am using ASP.NET and C#.
1
vote
2answers
450 views

HTML encoding to protect against XSS

While going through some references about protection against XSS i found that it is a good practice to encode data (entered by users) before using it to generate a dynamic page. I was not able to find ...
3
votes
2answers
318 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 ...
1
vote
1answer
308 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.
12
votes
2answers
906 views

How do I use Markdown securely?

How do I use the Markdown library safely? What do I need to do to make sure that its output is safe to include into my web page? I want to allow untrusted users to enter content (in Markdown ...
3
votes
4answers
744 views

XSS : Content-type: application/json

Background information - Application responds to request to a particular URL with content-type: application/json JSON response contains a parameter from the request Escapes the quote with a slash ...
7
votes
2answers
583 views

Interpolique: transparently preventing SQL Injection and XSS with base64 encoding, what happened?

For the keynote at The Next HOPE a couple of years ago, Dan Kaminsky unveiled Interpolique (the talk is really fun btw). The problem he raised was how to defend against injection attacks, including ...
2
votes
2answers
116 views

For untrusted user upload sites: what should the contents of crossdomain.xml and clientaccesspolicy.xml be?

Flash has a long history of ignoring MIME types of files and reading the file directly for executable content or for cross domain execution permissions. That means a malicious user can take advantage ...
3
votes
2answers
404 views

Is this an example of XSS attack?

A scripter sees on certain web pages it's technically possible to include markup like HTML and CSS/JS. It's technically possible to submit a javascript or iframe and have it display to the visitor ...
5
votes
4answers
525 views

Is XSS dangerous in application without database?

I think it definitelly isn't, because XSS which isn't saved anywhere would damage ONLY attacker. Am I right or are there any cases where XSS could hurt non-db-application? (I mean datas are not saved ...
11
votes
5answers
1k views

Solution to allow JavaScript input but prevent XSS

We have a simple Blog system that allows users to input html and JavaScript to build a blog page. I'm aware that allowing javascript open up the door to xss attacks. We do however need to allow users ...
9
votes
2answers
482 views

Cross site scripting verification on a field which does not accept more than 20 characters

While performing penetration testing, I got stuck to a point. There is a text field which does not accept more than 20 characters(server side validation). I inserted following piece of code to check ...
3
votes
2answers
1k views

How to protect from new Javascript Injection technique that doesn't use eval()?

There is a new Javascript injection technique that is generating chatter on the forums mentioned here Here is the code sample: String.prototype.code = function(){ return (new Function('with(this) { ...
8
votes
2answers
471 views

Recent Facebook XSS exploit details

There was a recent XSS exploit on Facebook that posted a vulgar message and got users to click on a link to spread the payload. What vulnerability was exploited, and what can other sites do to avoid a ...
5
votes
4answers
1k 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 ...
13
votes
4answers
748 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 ...
3
votes
3answers
287 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
309 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
118 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 ...
3
votes
2answers
3k 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 ...
3
votes
3answers
775 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 ...
0
votes
1answer
166 views

Replicating javascript actions from different website (XSS?)

I've got html / javascript code on my site like this: <a ...
3
votes
3answers
269 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) ...
9
votes
2answers
2k 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: ...
43
votes
6answers
3k views

Can anybody explain XSS to an idiot?

That idiot being me, of course. 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 ...
6
votes
4answers
858 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 ...
8
votes
7answers
915 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 ...
30
votes
4answers
2k 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, ...
19
votes
6answers
308 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 ...
13
votes
3answers
673 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 ...