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.

learn more… | top users | synonyms

1
vote
2answers
1k views

Can XSS vulnerabilities present in 3rd party js libraries be used to attack the app that uses the lib?

I am using various 3rd party libs like cordova.js, jquery, jquery mobile, mobilizer and so on, in a an android mobile app.. These libs are found to have various XSS vectors through insecure use of ...
11
votes
2answers
513 views

What should I look for when auditing a Firefox extension / plugin?

I've been asked to do a security audit on a Firefox add-on developed by a third party. I am a web developer with a reasonable grasp of JavaScript but am not a browser security expert. What kinds of ...
0
votes
1answer
344 views

How can I ensure privacy when outsourcing authentication to an IdP (Identity Provider)

I need to outsource authentication to an IdP (Identity Provider) but I don't want that IdP to know of the calling site. The two major issues are the callback URL and the referer header. Is there any ...
5
votes
2answers
8k views

DOM Based XSS attacks: what is the most dangerous example?

I knew that XSS attacks (“non-persistent” and “persistent”) can hijack user session, deface websites, conduct phishing attack, etc. However, I can't understand what is dangerous of DOM Based XSS if ...
1
vote
1answer
928 views

“pagesinxt.com” links in the sourcecode, am I being hacked?

At this moment I am being hacked and I do not know to stop it. Let me explain... My website is hosted in a VPS where I am the only person who has access to it. The page is builtwith ...
1
vote
4answers
3k views

Can JavaScript be used to install malware?

Looking at the Pwn2Own contest got me thinking: http://arstechnica.com/security/2013/03/pwn2own-carnage-continues-as-exploits-take-down-adobe-reader-flash/?comments=1 If you have all plugins turned ...
2
votes
1answer
577 views

Newline XSS vulnerability

So I was experimenting with XSS using new line (%0A) character. So I got to the usual vector: '%0Aalert(/xss/)// and one thing came to my mind. What if you can't insert a quote? A new line will break ...
2
votes
1answer
119 views

Return AWS signature over HTTP

I am performing multipart upload to S3 straight from the browser, i.e. bypassing my back-end. My JS code sends a hand-shake request to S3 (a POST), then uploads the file in chunks of 5MB (a PUT for ...
2
votes
1answer
402 views

Can a Javascript - WebGL proof of work system prevent website spam?

Is it a good idea to come up with a Javascript-based Proof of Work system to reduce spam on forums, and other websites? This idea would be similar to HashCash, but the computation would be based on ...
-2
votes
1answer
395 views

When logging into a web page what exactly happens when a user types the wrong password?

I have two related questions as to what happens when a user tries to log in to a website If the entered password is wrong what should happen? I have two ideas: Redirect to a page saying "wrong ...
4
votes
1answer
250 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 ...
16
votes
3answers
2k views

What security risks does Firefox 19's built-in PDF reader (pdf.js) bring?

Firefox 19 ships with pdf.js as the default PDF reader. One of the main stated goals is to reduce the exposure of users to the often vulnerable Adobe PDF reader/plugin. So what new risks does pdf.js ...
1
vote
1answer
185 views

Web speech API security

Does the web speech API send the audio to a third-party web service in order to do the speech-to-text conversion, or is everything built into the browser? I'm trying to work out how secure this API ...
2
votes
2answers
319 views

What are the security risks when users upload their HTML and javascript to AWS S3 and the content is used in a webapp?

I'm building this web app where users can login and build their own online presentation. To build the presentation they can use their own html, css and javascript. These user files are not uploaded to ...
4
votes
4answers
2k views

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 ...
2
votes
1answer
652 views

Black box testing javascript MVC web applications

I want to test a web application that has been built using the backbone.js framework. Currently I have used a few tools for crawling and testing without any luck. When crawling the website they can ...
7
votes
5answers
10k 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 ...
3
votes
4answers
597 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 ...
3
votes
2answers
2k views

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, ...
3
votes
1answer
523 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? ...
-1
votes
1answer
371 views

how to secure my login user id and passwords specially for facebook [closed]

i think they hack me with facebook cookies. i dont get what exactly is going on with me. every time i get the login notification from another ip location.i want to secure my cookies and i wanted to ...
1
vote
2answers
918 views

HTTP Response Splitting

Is this apart of a HTTP Response Splitting attack ? Here below is some code that gets put into a web browser after clearing the url while on the website javascript: var xhr = new XMLHttpRequest(); ...
3
votes
4answers
100 views

What is the technique to determine if a user is “reading” a page called? (similar to “infinite scroll”)

When I read an article at Salon.com I notice that the "overflow content" (where I need to scroll down) is loaded on demand. I can't imagine this being a useful bandwidth savings technique, so the ...
1
vote
2answers
291 views

Is a browser with disabled scripts and disabled java enough against malware

Is a browser like Firefox with disabled scripts (for example via a plugin like no-script) and disabled java enough to be protected against dryve-by-malware from the internet. Of course this does not ...
-1
votes
1answer
189 views

Idea feedback wanted - easy and secure web notes manager (javascript) [closed]

I have an idea for a web app that I'd like to discuss. I like it a lot but chances are that I missed some evident security hole. Or, maybe it just sucks. The idea is a web-based secure text notes ...
3
votes
2answers
509 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 ...
7
votes
5answers
25k views

Playing with Referrer Header

There are 2 sites: http://www.site1.com http://www.site2.com http://www.site1.com contains link to http://www.site2.com as <a href="http://www.site2.com/">link<a/> When user clicks ...
1
vote
1answer
153 views

How does window.w3ssss hack occur

Recently a .Net MVC 2 application on our server was infected with a virus / hack, it added some Javascript to the index.aspx pages of the site. While we have cleaned it up, I have not been able to ...
1
vote
2answers
1k views

How do I holistically protect a web service from network and MITM attacks?

I have several financial web services that are accessed over HTTPS, however the client devices may be accessing the web services over untrusted WiFi, through questionable proxies, and possibly ToR ...
4
votes
4answers
6k views

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 ...
10
votes
1answer
809 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 ...
8
votes
3answers
214 views

Preventing user supplied javascript from posting to external server

I am writing an internal tool that will support plugins written by other developers. Ideally, these plugins would have a Javascript component to allow people to make widgets. Some of the pages these ...
4
votes
2answers
149 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 ...
3
votes
0answers
69 views

Is the use of JavaScript for cryptography ever appropriate in the browser? [duplicate]

Possible Duplicate: How secure is aSSL (javascript)? Does it effectively mimic SSL? After some searching around, I realized we don't have an easily visible canonical question about this on ...
3
votes
1answer
384 views

How can I use certificates to secure my webservices? What is available to javascript?

I have a few web services that are accessed over public wifi connections and I think it would be a good idea to issue certificates to encrypt data, prevent MITM, and invalid impersonation (beyond what ...
2
votes
4answers
1k views

Are malicious scripts in batch files detected by antiviruses?

we have many scripts in shared folders in our IT Department. Are malicious scripts in batch files detected by antiviruses?
4
votes
4answers
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 ...
2
votes
2answers
322 views

I need explanation on how serious these vulnerabilities are?

I have found two vulnerabilities on my college site and I want to report them but don't know if these are "really" vulnerabilities : RFI inside SWF file. Example: ...
13
votes
3answers
1k views

How secure is aSSL (javascript)? Does it effectively mimic SSL?

Some of you may be familiar with the aSSL project, which uses AJAX/PHP to mimic the SSL protocol. It uses RSA 512 or 1024 for the keys, and AES for the actual data. It looks impressive to me in ...
5
votes
4answers
692 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 ...
3
votes
2answers
488 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 ...
5
votes
1answer
423 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 ...
0
votes
1answer
1k views

How to escape user input in a value of javascript object?

How to properly escape user-controlled input when it's inserted as a value in JSON object? <script> $(document).ready(function() { new MyObject({ key1: "user_input", key2: ...
8
votes
1answer
5k views

Iframe javascript Keylogger

Is it possible for a website to have a javascript keylogger and also contain an iframe that goes to a "client" site. Can the the JS log all key strokes done on the client site? Can the (host) iframe ...
7
votes
4answers
298 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 ...
10
votes
5answers
5k views

How to validate if a JavaScript library is secure?

I'm the main developer for an Open Source JavaScript library. That library is used in the company I work for, for several clients. Every now and then there is a client that feels paranoid about ...
9
votes
2answers
689 views

User-specific Subdomains : JavaScript security

If I provide a public-facing website for users on my website at their own subdomain (e.g. bob.myapp.com) under their own control, can I allow them to execute arbitrary JavaScript without putting my ...
-1
votes
4answers
183 views

How secure is this login page? [closed]

Unfortunately I cant link to the page (it internal). But I can describe it! This is a lightspeed systems policy enforcement login page (content filter). The page is http and there is no iframe with ...
5
votes
3answers
5k 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 ...
2
votes
1answer
2k views

How to prevent the following clickjacking attack?

The Security attribute was implemented to prevent XSS attacks in iFrames by disabling any JS implemented in the iFrame source, therefore indeed eliminating XSS attacks, but also disabling any security ...