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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Is it possible to create a secure chat web application relying on HTML5 web sockets?

Is it possible to create a secure chat web application using just HTML5 and Javascript? What possible security holes would there be if the server doesn't store the messages, just relay them using ...
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3answers
521 views

Are CSRF Attacks Really Blind

I'm new to CSRF attacks but don't see how they are always blind. Let's say we are dealing with a site where the asset we need to protect is the HTTP response. Something like one's medical history. ...
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1k views

Web & insecure HTTP - Using RSA for encrypting passwords on the client side

I used client side password hashing in my register and login project. Its purpose is to prevent passive adversaries/eavesdroppers from discovering users' plaintext passwords when HTTP requests are in ...
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Is a JavaScript implementation of AES any less secure than other language implementations?

There are a few JavaScript AES implementations available such as Gibberish-aes So assuming the AES algorithm has been implemented correctly in this library then it should be as secure as any other ...
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758 views

Is JavaScript self-injection dangerous?

I have a toy web application that can be described roughly as a per-user key-value store. After logging in, the user can view and modify her set of key-value pairs. The keys and values are stored in a ...
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828 views

What are NoScript surrogates and should one disable them for more privacy in browsing?

NoScript has a feature of supplying its own "surrogate" scripts instead of well-known tracking/ad scripts (Google Analytics, for one). Does it matter for my privacy if I do not change the factory ...
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194 views

User entered Javascript security implications

I'm creating a web site that lets people create their own site using a subdomain. Are there any security implications by letting people add custom javascript to their pages? If so, which ones? XSS? ...
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7k views

Javascript Malware: How does it work, and how can it be mitigated?

I am wondering how malware gets served through Javascript. I've noticed a few illegitimate pop-ups while visiting some financial websites. I wonder how malware exploits work against the application ...
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182 views

Is it safe to allow untrusted field names in JSON?

When forming a JSON data structure, are there any security risks with allowing the field names to be chosen by an attacker? You can assume they'll be quoted properly. I'd like to know if allowing ...
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1answer
134 views

Are there cases where malicious scripts on websites breached the sandbox of a browser so that files on the user's computer could be accessed?

Whenever a hosted script on a website tries to access a file on a user's computer the sandbox prevents it, but has there been any documented case where this sandbox obstacle was somehow overcome by ...
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6k 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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170 views

Protection against synthetic queries

Note: One, I am not sure if synthetic queries is right word for the risk I am talking about. Second, though I am considering 3-tier model of web-applications general answers are welcome in ...
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759 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, ...
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1answer
488 views

Using javascript, is it possible to iterate through all cookies saved in the user browser and send them to me?

Again, I am new to the programming and security world. I should mention that it is just a theoretical question so I can anticipate this kind of attack. Using javascript, is it possible to iterate ...
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1answer
41 views

Does prefetching/preloading in web browsers pose a security risk?

Today I googled the name of a domain that was reportedly serving up malware. My search results came up (with the compromised domain at the top of the list) and within seconds my AV gave an alert ...
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1k views

XSS using JSF**k

I was reading about JSf**k. From their website: JSF**k is an esoteric and educational programming style based on the atomic parts of JavaScript. It uses only six different characters to write and ...
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2answers
1k views

Is it safe to use createHTMLDocument to sanitize HTML?

i'm wondering how safe it is to use createHTMLDocument to do HTML sanitization. I've tried to implement it like this: function sanitize(string) { var elm = ...
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2k views

Problems with avoiding JSON hijacking with MVC3's AntiForgeryToken, or similar token validation

I'm hesitant to implement the proposed anti-JSON hijacking solutions since The recommended solutions to mitigating JSON hijacking involve non-REST-full JSON POSTs to GET data The alternate ...
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1answer
91 views

Random Oracle in Javascript for password generation and recall

I use a lot of different sites, and my number one security issue is to never reuse a password. As it seems that every company out there like TalkTalk is as leaky as a sieve, I figure that's the right ...
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1answer
141 views

Video site requests Adblocker to be shut off, next day I have 3 “weird” bookmarks

I was on a site trying to view a video and the site requested that I turn off my adblocker to view the video. So I did and then the next day I noticed that I had 3 "weird" bookmarks in my bookmark ...
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2answers
808 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
420 views

Exploit SoakSoak injected in Wordpress

I have recently received an attack to my website and Google is warning visitors to not load the page. The malware is located in wp-includes/js/swfobject.js of my Wordpress and I had deleted it but ...
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69 views

What to use as 'state' in OAuth2 Authorization Code Grant workflow

I'm using csrf protection in my web app. Now I'm planning to trigger a OAuth2 Authorization Code Grant workflow, starting with a static template opened in a new browser window using ...
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1answer
485 views

Cufon or Prototype as an attack vector for Blackhole exploit kit?

I've been asked to look into the security of a client site that's apparently throwing antiviral messages when visited. Specifics: It's being detected as a Blackhole exploit kit inside of a Cufon ...
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278 views

What to do when iPhone is successfully phished

My girlfriend watched "some" pages on her iPhone and facebook.you-won.com page appeared. She didn't know how to get rid of that JavaScript alert, so she clicked OK. After that she closed the page, and ...
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274 views

Safe to render data directly to DOM from localStorage? XSS attack possible?

I read that localstorage is susceptible to XSS attacks. I currently store JSON Web Token (JWT) in localstorage, and I access and display data about the user through localstorage: var localstore = ...
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Is 'Forge' Javascript crypto library secure? [closed]

I need a client-side crypto library. I've seen https://github.com/digitalbazaar/forge linked many times on stackexchange. Forge seems to be the most complete and well-documented crypto library for JS. ...
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2k views

Could a malicious JS file pointed on URL/URI attack the browser/computer?

I found some website blacklisted on Google. I mean when you try to visit them, you get something like shown on this picture: After a small search, I found that some of them have a malicious ...
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1k views

Is it possible to make an xss with only html tags

I'm not aware of all the xss tricks.. While programming in Ruby on Rails, using a sanitize method to allow only certain tags and it makes its best to clear all the other tags and scripts the ...
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5answers
218 views

Avoid unauthorized updating of online leaderboard php/sql [duplicate]

I am developing an offline web app (game) for android using cordova (phonegap). The leaderboard of the same is maintained online in my server. Currently this is how the leaderboard is updated Step ...
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2answers
648 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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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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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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2answers
766 views

Predicting Math.random() numbers?

I was reading up on the documentation for Math.random() and I found the note: Math.random() does not provide cryptographically secure random numbers. Do not use them for anything related to ...
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2answers
1k views

DOM XSS attack failing in Firefox

I am trying to perform DOM XSS attack to exploit a vulnerability of localhost webpage. I am able to perform the attack successfully on IE-11 and Chrome. But Firefox is preventing me to perform the ...
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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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XSS cookie stealing without redirecting to another page

I'm practicing in VM following the OWASP guide. I know that is possible to steal the cookie by redirecting to "False" page etc. but I would like to steal the cookie without redirecting on another ...
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3answers
16k views

What typically is the expiration date of a session cookie?

I need to create a session cookie using JavaScript (for more info see question). I'm wondering what should the expiry date be? I'm guessing it's the browsing session, so if I don't set an expiration ...
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589 views

Is flash or javascript a bigger security concern? [closed]

Many flash website whitelisting extensions for chrome (such as flashblock and flashcontrol) use javascript in order to selectively block Adobe Flash from functioning. Thus, In order to get this ...
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2answers
761 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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2answers
3k 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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3answers
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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2answers
290 views

Is it neccessary to use X-FRAME-OPTIONS to prevent ClickJacking attacks?

I use this Javascript Code, and it works perfectly: if (top.location != location) top.location.href = location.href Many researchers told me to not use this. Can any one bypass it? Are there ...
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1answer
11k views

Create RSA public, private key pair having numbers generated already

I want to know to to generate working RSA key pair, with correct syntax. Let's say i have already generated somehow my numbers for 512bit key, which are: e = 00065537 d = ...
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2answers
1k 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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1answer
377 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
152 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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807 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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2answers
101 views

Stopping webpage compromise by preventing frame-busting

My website offers rich content to users. I often subscribe to third party vendors whose content I embed in my pages. How can I safely embed external domain's content on my webpage in an iframe without ...
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1answer
6k 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 ...