0
votes
1answer
135 views

Why is it a bad idea to escape HTML before escaping SQL? [duplicate]

From the security perspective (and not usability as it's discussed here http://stackoverflow.com/questions/3648430/is-it-a-bad-idea-to-escape-html-before-inserting-into-a-database-instead-of-upon), ...
2
votes
3answers
191 views

OWASP escaping recommendation - why /?

In OWASP recommendations regarding escaping untrusted input for HTML element content, they list the following: & --> &amp; < --> &lt; > --> &gt; " --> &quot; ' ...
34
votes
4answers
5k views

Should websites be allowed to disable autocomplete on forms or fields?

Currently, there is an HTML form/input attribute called autocomplete, which, when set to off, disables autocomplete/autofill for that form or element. Some banks seem to use this to prevent password ...
4
votes
2answers
216 views

Escaping rich text editor output

When having a rich text editor on a web application, what is the best way to escape HTML entities and prevent XSS attacks but keep the formatting (<b>, <i>, <u>, ...etc.) ?
5
votes
2answers
129 views

Any eventhandlers that apply to hidden elements?

Im trying to XSS a search field and my attack vector is getting reflected like this: <input type="text" id="txtRpHiddenKeyword" style="display: none;" value="ATTACK VECTOR HERE" /> Only ...
2
votes
3answers
1k views

Javascript containing a long hexadecimal string and eval: is this suspicious?

At the bottom of the index.php file for a simple “contact us” form, I found the following (some whitespace and newlines added): try {if(window.document)--document.getElementById('12')} catch(qq) ...
3
votes
1answer
316 views

How can I check the iframe on my website is secure or not?

My website has an iframe used for loading my client's websites (only 5).How can I make sure the iframe is secure? Also by editing iframe src It allows to load any other websites.How can I prevent it?
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 ...
7
votes
1answer
1k views

What possible use does an iFrame have for security?

I'm looking at code for an old login form I'm redesigning. It's a simple table with two input fields for username and password. But just before the end </table> tag there's a blank iFrame which ...
2
votes
4answers
810 views

Simple solution to XSS

I've got an idea as to how to defeat XSS so simple that it may work and was wondering if anybody had already done something similar. The goal here is not efficiency but security. In other words I ...
1
vote
2answers
399 views

Breaking out of attribute in double quotes

I have a piece of code that allows for [url]someurl[/url] BB-Code and replaces it with <a href="someurl">someurl</a> It takes two precautions to prevent XSS. It replaces ...
12
votes
3answers
527 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 ...
10
votes
1answer
644 views

How can I embed iframe securely without restricting its functionality?

I'd want to embed an iframe from untrusted site into web application. Iframe: should be able to run Javascript and browser plugins (Flash, etc.) should not be able to access my web application ...
7
votes
4answers
241 views

Limited JavaScript app scenario: Attack vectors and mitigation

I'm going to be developing a single page JavaScript app which allows input via a textarea. This input is never sent to the server, never shown to another user, and will only be persisted in browser ...
1
vote
5answers
1k views

Is it secure to use jQuery on the server-side for user input validation?

I'm thinking about using jQuery on the server-side (node.js) to validate user input (filter tags, remove every attributes except href, rel, target & style, modify css rules which are applied ...
2
votes
4answers
352 views

Clickjacking: can't browsers just forbid/reject placing transparent elements over frames?

Why not? Seems like this is only used for clickjacking, the solution should be simple enough.