The common name for the language used primarily for scripting in web browsers. It is not related to the Java language. Standardized as ECMAScript, its dialects/implementations include JavaScript and JScript.

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How to prevent attacks against client side validations?

I have a login form where am accepting Mobile Number of the User for login. When Mobile Number is submitted, am calling a JavaScript to validate the Mobile Number. My client side validations ...
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What does scorecardsresearch.com/beacon.js - added by Disqus.com - do?

I recently added Disqus to my site. Looking at the "scripts" tab on Firebug, I noticed a script called, http://scorecardresearch.com/beacon.js (here is a prettified version - the script is not ...
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2k 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) { ...
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983 views

Clicked on fake “Download Now!” ad on file transfer site (legal file for legit purposes) by accident; does anyone know what measures I should take?

I was sent a file by a coworker via "sendshare" - my first time using the service. The page loaded a bit slowly and the ads came in before the actual download link. I was in a hurry to get the file - ...
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543 views

Can one get infected through visiting a site with a PHP script on it and if yes, how?

I can imagine a clientside JavaScript that gets executed in a vulnerable browser to do some harm, but how can this be done with PHP? Since it's serverside it shouldn't have access to the visitor's ...
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Javascript Diffie-Hellman and AES protocols

I am using the BigInteger Javascript library to create a symmetric key using Diffie-Hellman protocol. I want to create 128,160 or 192-bit keys. After some research, I have found out that I should use ...
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2k views

UTF-7 XSS attacks in modern browsers

I've recently read about utf-7 XSS-attacks (i.e. Ned Batchelders article at http://nedbatchelder.com/blog/200704/xss_with_utf7.html) but could not get any UTF-7 attack to work in modern browsers. (I ...
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508 views

Safety of using web based proxy?

Lets say for example I have to use a public online proxy like https://www.zend2.com to load a PHP webpage controlled by me containing sensitive data over HTTPS. How would I make sure that the proxy ...
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799 views

XSS: Parsing Javascript

Reading about DOM based XSS from http://www.webappsec.org/projects/articles/071105.shtml It illustrates some examples like: ...
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148 views

Can webpages recognize that I saved my password?

If you save your logins in Firefox, username and password are auto-filled-in in corresponding webpages as soon as you visit them (if you have more than 1 account saved, you'd have to select a username ...
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672 views

PHP/JavaScript with RSA

I have a few columns in the database which should be encrypted. I'm wondering if the way I chose to make this system work is ok, and I'm looking forward to hear some opinions: I chose RSA algorithm ...
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4k views

Is it safe to give an Oauth token to client side javascript so it can directly make requests to a server?

I currently have a simple backbone.js application served from my domain (example.com), which is provided an Oauth token. Specifically, I pass the Oauth token through my page template into the ...
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245 views

Potential issues with Kim Dotcom's new proposed “encrypted webmail service”

Just spotted a Reddit thread about Kim Dotcom, of MegaUpload fame, planning to produce a secure webmail system that allows people to communicate securely, without the worry of having their messages ...
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144 views

To What Extent does an Attacker Have Access to the Browser History through the CSS Pseudoclass :visited Styles?

I have read this article on how a scripted web page is able to obtain the visited history of a user browsing the page. However, I can't find any clear information in the article describing the extent ...
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123 views

Security consequence of Javascript hole in an online chat?

For an online chat that allows basic HTML, what happens if they leave an open way for a potential hacker to execute javascript on everyone who is in the chat? What is the worst thing they could do?
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441 views

Are sandboxes overrated?

I've stumbled upon the following on the blog of the NoScript developer Giorgio Maone. First, he quotes the following ArsTechnica article about an XSS bug in Adobe Flash: As useful as sandboxes ...
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164 views

Suspecious js file sent as email attachment

I received a js file with following code in my spam folder but I decided to take a look into the file. Do anybody of you know what does this code might do? var evl='';function nr() { evl = '}; ' + ...
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312 views

How can document.referrer be used for XSS?

A very simple example... <div id="cat"></div> <script> document.getElementById("cat").innerHTML = document.referrer; </script> or <script src="' + document.referrer + ...
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1answer
865 views

OWASP Recommendation on Client-Side Password Hashing

The OWASP Application Security FAQ recommends the use of JavaScript to produce a salted hash of the password client-side with JavaScript prior to sending it to the server. Is this something truly ...
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89 views

Should I be worried about this url request I received on my site?

I was checking the weekend logs of my IIS server and noticed a strange request which was blocked: ...
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1answer
797 views

How should I mitigate the XSS vulnerabilities in KnockoutJS described at mustache-security?

The site Mustache-Security describes XSS vulnerabilities in KnockoutJS... The vulnerabilities come from the use of eval (or some equivalent) to convert text in the data-bind attribute to executable ...
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1answer
331 views

How secure is JavaScript based OAuth 2.0

JavaScript based OAuth exposes the client ID of the application and it trusts only on the domain requesting the access token. The domain name can be forged with a DNS hijack (or a virus affecting ...
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265 views

Why would a user agent string be executed?

I'm having trouble understanding how a particular XSS vulnerability might arise in the real world. Guides for two of the exercises on hackthissite.org: ...
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9k views

Hiding JavaScript source code

In a web-app should one strive to hide as much of the code as possible, for example from view source? In particular I was wondering should JavaScript be hidden, especially ones used for Ajax? I was ...
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Is XSS possible here? Challenge

Is possible to bypass my regex and execute any javascript? <script> function json(a){ if (/^\s*$/.test(a) ? 0 : /^[\],:{}\s\u2028\u2029]*$/.test(a.replace(/\\["\\\/bfnrtu]/g, ...
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How to stop other website to send cross domain ajax requests?

From 2 different applications, I was able to send cross-orgin requests. Though the browser return an error of Cross-Origin, but my server is still receiving and executing the request. For example, ...
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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 ...
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612 views

Stop code injections into page code

I started a topic HERE on the stackoverflow site, but was refered here. I did get some info there, but think it need's more indepth input. So hopefuly people here can help. I have a few domains ...
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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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744 views

How can JavaScript be tampered with while viewing a web page?

I often hear about how client side JavaScript can't be relied on because it can easily be changed. How exactly can it be changed, what program would be used to modify the JavaScript before a page ...
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1answer
496 views

Is this code harmful? Why?

Code: http://pastebin.com/kJ8ZGP82 That code gets retrived from http://ui.sidepage.co for every HTTP page I visit (not HTTPS) and load it into the body tag of the page. Is it harmful in any way? ...
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717 views

HTML Vulnerabilities

My question is three-fold. Background I was asked to do some vulnerability scans on a website with some holes (I think). On a particular page, I was able to escape the text field and write on the ...
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482 views

Is it possible to see if a script on a website steals session cookies?

I'm looking as some web analytics solutions, I know it sounds paranoid. but cookie-based web analytics need for you to paste their JavaScript code on your web-site. I don't like the idea too much of ...
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7k views

Why is JavaScript disabled in the Tor Browser Bundle?

Didn't Tor create a local socks proxy? Why doesn't all the Web traffic go over this local socks proxy and why is JavaScript disabled in the Tor Browser bundle? If you would connect with firefox for ...
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549 views

How can I constrain or limit 3rd party Javascript (*.js) files that can DOS my site?

Many website owners integrate Google analytics, various Facebook or Twitter social media javascript plug ins into their web pages. The problem is that this trust seems to be "all or nothing", meaning ...
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2answers
577 views

Why do I get AV alerts when browsing a web page?

I'm using the latest version of Firefox and Windows is up to date. When I was browsing a webpage and clicked a link the browser displayed "connection has been reset" and AVAST poped-up saying "Alert!" ...
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381 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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452 views

Can a whitespace regex character be used to perform a javascript injection?

if I want to validate the input of a <textarea>, and want it to contain, for example, only numerical values, but even want to give users the possibility to insert new lines, I can selected ...
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4k views

Facebook spam / phishing attempt?

I got this sent by a friend on facebook and i dont think its a genuine message ___ shared a link on your Wall. This will leave you speechless) ...
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352 views

Injecting information in a web page (Gmail). Does it raise security problem?

I am developing a Google Chrome extension which encrypts/decrypts emails for Gmail users. So, I detect encrypted emails when the user opens an email on using tags. Once an encrypted email has been ...
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1answer
316 views

Security of Javascript in mobile browsers

Is Javascript on a mobile browser more secure than Javascript on other types of systems? For instance, if I have a site that includes some client-side (Javascript) encryption code, with the intention ...
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2answers
538 views

Implementing brute force attacks on hash values in Javascript

I'm working for my bachelor thesis at the end of which I aim to implement a proof-of-concept Javascript-based hash cracker. The idea is to work like this: Users can submit a hash value along with ...
3
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1answer
218 views

Content not appear in body

I have a file a.html, which has the following content: <script> var x=document.URL.substring(document.URL.indexOf('#')+1); document.write(x); alert(document.body.innerHTML); </script> ...
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1answer
101 views

How does the same-origin policy apply between browser tabs? [duplicate]

Let's assume that we have 2 open tabs in a browser containing page A (A.html, A.js) into the first tab and page B (B.html, B.js) into the second tab and that page A and B have the same origin (scheme, ...
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806 views

SJCL : convert ascii to a BitArray & compute random numbers

I am using the Stanford Javascript Crypto library and i'd like more information about it. 1.) I have an ASCII text and a random 128-bit key. I want to concat those two things, so I convert the ASCII ...
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1answer
3k views

Can your Windows or Linux username be exposed to websites?

For example: Accessing a website with javascript enabled can expose information such as browser, fonts and local time. Can it, theoretically, expose your Windows or Linux username? Will saving a ...
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436 views

Should the Keygen element be used to create a certificate for mutual auth TLS? What alternatives are there?

I'm interested in using mutual auth TLS to improve the security of my javascript based webservices . I've looked at the Keygen element and given all its issues, not sure if this can even be used for ...
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58 views

Why browsers implement stricter policy for local files

I have a problem viewing HTML/JS/CSS files generated on disk. Specifically, several calls in javascript are blocked by Google Chrome. I googled and found an answer here: ...
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1answer
196 views

Javascript client side image decryption, does this add any safety or is it flawed

I want to store passport copies safely in a database, the database itself is a normal MySQL database and on a somewhat trusted web server. The user who owns the passport copy should only be able to ...
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1answer
208 views

Danger of hidden html form uploading users local files without their knowledge

Is there a danger that a webpage could have a hidden form with a file upload input and js script that would try and take a random guesses at files on a users system and attach them to the form and ...