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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0
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1answer
26 views

Malicious JavaScript warning

I visited a site yesterday and received no malicious javascript warnngs. Today I visited that same site and got the warnings. Do I need to be worried about being infected with something?
3
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1answer
48 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 ...
20
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2answers
2k views

Does browser 'view-source' mode avoid scripting attacks?

Let's say there's a URL www.badjs.com which is untrusted and may contain bad scripts. Intuitively, a view-source navigation to that URL does not execute any scripts so it should be safe. It would at ...
0
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2answers
35 views

Is it safe to log JavaScript exceptions to the error console?

I know that on the server side it's very bad to display system-level errors instead of logging them to disk, because it could expose potentially sensitive information, but do the same concerns apply ...
0
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1answer
102 views

Is there any security benefit in stripping only `<script>` tags that contain code?

On a client's corporate network something is stripping all <script> elements that contain code, i.e. things like <script type="text/javascript">do_something();</script> will simply ...
1
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0answers
45 views

Pre-internet encryption for a rest application

I have a project idea that I want to code. There will be a huge gain for my user to be able to use it over a website and on their mobile device. The problem is the data will contains financial data ...
1
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2answers
42 views

Temporary XSS Vulnerability

I found xss on a textarea field. When you enter a character to this field it output the character on realtime so when i input the following code: <input onclick=alert(document.cookie)> there ...
3
votes
1answer
98 views

How can I successfully perform an xss attack on a dummy website? [closed]

in my security course, we were told to practice an xss attack using firefox on this website; http://permalink.co/ No worries, this is a website specifically setup for us to practice ...
-3
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0answers
14 views

Php's password_hash encoding for HTTP basic authentication [migrated]

My problem: I need, basic authentication over HTTP (client can't afford HTTPS). So I don't worry if communication is not encrypted. I just want to prevent some user from sniffing and using the ...
0
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2answers
97 views

Source code disclosure vulnerability

I am a bit confused about the discussion here about hiding javascript source code. Let's say if I browse to a url like this: http://www.example.com/site/somejs.js and then what I see is something like ...
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2answers
55 views

Using DNS to track browser activity on a LAN

I am trying to create a small network auditing script that tracks HTTP and HTTPS domain names visited by certain hosts using the libpcap wrapper for Nodejs. At its best the script would be able to ...
2
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0answers
14 views

How to Allow users to save html in Rails application without affecting security [duplicate]

After doing a lot of research I come to this forum hopefully i can get some help. I am building a Ruby on Rails application (version 4.2) My app allow users to create "one page" portfolio : user 1 ...
1
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1answer
66 views

Cross Domain Javascript security [duplicate]

I used a web vulnerability scanner to scan my web site. It indicates several links with "Cross domain Java script source file inclusion." May I know how would an attacker exploit this type of ...
0
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0answers
46 views

Best practices to invalidate JWT while changing passwords and logout in node.js?

I would like to know the best practices to invalidate JWT without hitting db while changing password/logout. I have the idea below to handle above 2 cases by hitting the user database. 1.Incase of ...
2
votes
1answer
39 views

Limiting latter dom-based XSS when setting document.title

Given some JavaScript which modifies the page's title by taking in variable data document.title = someVariable I am looking to address dom based XSS while keeping the title fairly readable. ...
2
votes
1answer
65 views

Securely identify clients by web app

I have a web service S that provides certain services. There are two web apps, A1 and A2, both on different servers within the same VPN, which I trust and want to grant access to my web service. ...
0
votes
1answer
27 views

Secure keyboard entry with JavaScript or Flash?

Is it possible to perform secure keyboard entry (similar to what is offered in the OS X Terminal app) using only web technologies and/or Flash? If not, is there any way to more broadly guarantee ...
0
votes
1answer
56 views

How can I secure my server to ensure pre-login calls are originating from my app?

I have a .NET Web Api servicing a Cordova based mobile app and web front end written in AngularJS. I have done a ton of research and most sources don't give a great answer or one that's huge overkill ...
1
vote
2answers
105 views

XSS outside of the DOM

I have the following JS (using jQuery for brevity's sake but it isn't necessary for the question): $("<i></i>").html(userInput); Is it possible for someone to input some string, ...
0
votes
1answer
41 views

From a security perspective, why not a screenshot api for browser? [closed]

I mean a javascript api for capturing a renderered html page, or current viewport, and dump content onto an image. While there are obvious attacks, such as taking screenshot of sensitive information, ...
9
votes
2answers
2k views

How do the Stack Exchange sites protect themselves from XSS? [duplicate]

It seems to me that because Users can post questions and comments in them with HTML markup (possibly <script> tags), Stack Exchange sites would be very exposed to XSS attacks. How do they ...
2
votes
2answers
184 views

Website infected with unwanted “redirections”, apparently via javascript code

I'm working on a clients website, and I realize they've been compromised. Early today there was a major problem with a php eval(base64_decode issue. That was cleaned up via Andy Stratton clean.php ...
3
votes
1answer
97 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, ...
1
vote
1answer
134 views

Encrypted quiz data in PHP and JS

I'm developing a quiz with which you can win a few cool prizes. Therefore I'm afraid, that someone might try to hack/manipulate it. All participants have to be logged in and the website takes 15 ...
2
votes
2answers
111 views

High level design for secure web application

I'm looking for some advise on designing a secure web app for storing passwords. Why reinvent the wheel? Because I don't trust a 3rd party with all of my passwords. Here are my thoughts: There are ...
2
votes
1answer
105 views

How is the QSS tag used as payload in an XSS attack?

I have received a report from a client that lists XSS vulnerabilities. The report shows reflected XSS vulnerabilities. In each vulnerability, the payload reflected is a single, unclosed <qss> ...
0
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1answer
239 views

Preventing socket.join(“room”) client-side, listening for private room leaving

i'm developing an application with Socket.IO that needs to authenticate if user can join a room. Client side: var socket = io('http://<?php echo $_SERVER['HTTP_HOST'];?>:3000'); ...
2
votes
2answers
86 views

Security of Firefox extensions such as Mailvelope

I am asking these question because I am not very familiar with javascript or the Firefox plugin/extension system. The specific context is the Mailvelope pgp extension but the questions are general and ...
2
votes
1answer
45 views

Spoofing of Server Sent Events

In the spec for Server Sent Events, it says Authors should check the origin attribute to ensure that messages are only accepted from domains that they expect to receive messages from. Otherwise, ...
-1
votes
2answers
112 views

Is JavaScript console vulnerable to XSS

Assume the content of the name variable below is controlled by an attacker. Is this line of code vulnerable to XSS? console.log(name) When I send an injection in name variable I see its value ...
4
votes
1answer
162 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 = '}; ' + ...
5
votes
1answer
302 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 ...
4
votes
1answer
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: ...
49
votes
6answers
5k views

Does injecting querystring values directly into HTML pose a security risk?

Someone reported a bug on my site that I don't really consider an issue. My site has an URL akin to this: www.site.com/ajax/ads.asp?callback=[text injection] So filetype is application/json, and I ...
0
votes
2answers
105 views

How can this web server be compromised?

A linux server has Node.js installed with the http-server package. The server will respond to requests on port 80 with a file in the same directory named index.html. An interesting characteristic of ...
0
votes
1answer
114 views

Verify CDN javascript's integrity

CDNs speed up the loading of websites by allowing caching for frequently used javascript libraries like jquery. How do we know if they have modified the javascript before serving it to my clients? ...
1
vote
2answers
83 views

What's the best way to secure the responses in a single page web app after logout?

I've read some of the great responses to storing and passing session keys in a single page web application (i.e., a web "site" that runs mostly on the client-side, getting data from the server by ...
2
votes
2answers
112 views

is it sufficient to convert '(single-quote) to ` &#039; `

Is it sufficient to convert ' to &#039; , > converted to &gt; and < converted to &lt; to avoid xss A bit of context: the payload would be going through the URL and landing in a ...
1
vote
1answer
120 views

Attack using weird characters followed by some javascript in a URL?

I'm seeing a very weird attack this morning from a pile of VPS instances spread out across the US. The URLs look like this: /js/bundles/,!0):this.element.propAttr( ...
2
votes
5answers
593 views

Is converting `<` to `&lt;` sufficient to prevent execution of JavaScript from arbitrary HTML?

This is kind of a bar-bet question. An acquaintance of mine has made the claim that, given an arbitrary glob of HTML, it can be completely prevented from executing JavaScript if, before slapping it ...
16
votes
2answers
2k views

Can JavaScript be used to capture the user's screen?

Can JavaScript be used to capture the user’s screen? If so, is this functionality available in any JS framework? (I do not need code examples: I am mainly asking to form an opinion about the security ...
0
votes
2answers
307 views

What's the best way to authenticate an user using a websocket?

I'm creating a multiplayer game(based in websockets) which runs directly from the browser and which has multiplayer functionality. Each player needs to have his own account(Username and password). ...
1
vote
1answer
171 views

What are the security risks associated with PDF files?

What are the security risks associated with PDF files? There is, of course, the general risk associated with any type of file: that whatever application is used to read it will have a bug that can be ...
8
votes
2answers
1k views

Cordova/Phonegap: RefreshToken in localstorage

I am (partly) following a tutorial to develop a cordova app, based on angularJS. The author stores the refresh token in local storage, which was said to be very bad practice in one of the comments on ...
0
votes
3answers
583 views

bot detection via browser fingerprinting

I've recently noticed that a few companies have begun to offer bot and scraping protection services based on the idea of browser fingerprinting to detect them, and then blocking the specific ...
1
vote
1answer
120 views

Is it dangerous to allow clients to run JavaScript on a Server

On a webpage I have been working on, we can archive certain webpages for a user. The user can give an address and this webpage is than visited on the server and archived. Lately, I noticed that ...
3
votes
2answers
55 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: ...
0
votes
1answer
68 views

What are the major threats involved in storing the session identifiers in local storage instead of cookies?

I want to know the major security threats involved in storing the session variables in client side local storage, instead of storing it in the cookies. Can somebody give me a brief description?
1
vote
1answer
46 views

Javascript file detection

One common technique I use is xor bruteforcing on binary data. In this case, I would like a heuristic approach to determine whether or not any possible candidate plaintexts are javascript. This rules ...
0
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1answer
231 views

extracting JSESSIONID from document.cookie

I was trying cookie stealing on a java and spring based web application. Normally, a cookie can be obtained through <script>alert(document.cookie)</script>, but in the above code, cookie ...