Tagged Questions

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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3
votes
4answers
496 views

How is this XSS attack working?

SPOILER ALERT: This question contains an answer to one of the problems from the Google's XSS Challenge! Please stop reading further if you're not interested in knowing the answer right now. I'm ...
2
votes
3answers
128 views

XSS prevention by black-listing

I have a reflected XSS vulnerability in my Web application. I have decided to take the black-list approach instead of the popular white-list approach. My question is can there exist a malicious ...
2
votes
2answers
343 views

XSS in HTML meta tag

There is a web application which contains a search function. When I search for aaaaaaaaxss I get this: <meta property="the:property" content="100 Results for aaaaaaaaxss (Page 1)" /> It strips ...
2
votes
1answer
134 views

Should a space in a password count as a symbol when checking for complexity?

There is no doubt in my mind that spaces should be allowed in passwords. I see some websites disallow spaces, symbols in passwords and even enforce minimum length which seems t otally nonsensical to ...
2
votes
1answer
392 views

HMAC secret key client storage

I've read numerous articles about using HMAC and the secret key for client authentication in a RESTful client (Javascript) application today. Still, I don't find a single source that is able to ...
0
votes
1answer
431 views

How do I inject JavaScript into a JPG image and execute it when uploaded?

I've recently joined a security project, and received a task to demonstrate the risk related to an end-user uploading an image containing embedded (malicious) JavaScript code. I used EXIFeditor to ...
0
votes
1answer
110 views

Access-Control-Allow-Origin possible threats on static JS file

As I am working on a research, I need allow users to read my JavaScript file using Ajax. However, I want to make sure about consequences of adding Access-Control-Allow-Origin header for just this ...
5
votes
3answers
217 views

Secure a publicly accessible REST api

We're building a public single page app in JavaScript that talks to a back-end REST service. What we want is for that REST-service to be only accessible from the single page app. Since it's a public ...
1
vote
5answers
187 views

How to ensure that files uploaded by users do not contain any Javascript

I'm trying to make a file uploader using PrimeFaces, but it is vulnerable to scripts: If someone tries to upload a file (e.g. a résumé) that includes JavaScript, this could get executed once the file ...
1
vote
1answer
81 views

Detecting code source variants of the same function [closed]

Suppose I have this JavaScript malicious function f1() : <SCRIPT type="text/javascript"> function f1(){ a=1; b=2; c=a+b; } </SCRIPT> This function is embedded within a larger ...
3
votes
1answer
171 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 ...
0
votes
2answers
187 views

How dangerous javascripts really are? [closed]

I've watched this video, and what this guy says is that with javascript its easy to create a worm that steals your information also that javascript will continue to execute even tho you closed the tab ...
0
votes
1answer
219 views

Can I use crypto.getRandomValues to create a private key?

In the window.crypto spec: http://www.w3.org/TR/WebCryptoAPI/#RandomSource-interface It says explicitly: "Do not generate keys using the getRandomValues method. Use the generateKey method ...
1
vote
1answer
111 views

Securing Javascript plugin

My company offers a Javascript plugin that is meant to be embedded with websites. It works in a similar fashion to Google Analytics, in which you add a bit of Javascript and then it does some magic on ...
0
votes
1answer
246 views

JS malware detection

Is there a way to detect a malicious JavaScript code within a webpage before the script runs on my computer ? I want to develop a Python script that prevents from 8 JS malwares that I can embed on my ...
5
votes
2answers
245 views

Do Javascript malware signatures exist?

Are there signatures for malicious JavaScript codes as they exist for other viruses/worms/trojans developed in other programming languages ? If so, are these javascript malware signatures defined ...
1
vote
2answers
108 views

If I change any character in a private PEM, should the public PEM be different?

I'm generating a public PEM-format key from a private PEM-format key. I noticed that if I change a few characters near the end of the private PEM that the public PEM generated from the modified ...
2
votes
1answer
271 views

how secure is javascript based oauth2.0

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 ...
-2
votes
1answer
400 views

How to decrypt javascript code extracted from PDF

I analyzed PDF, and extract javascript code. But javascript code is encrypted. I can't decrypt it. Please advise me. javascript code ...
1
vote
1answer
943 views

Is it safe to use localstorage to store session variables and user password? [closed]

I'm trying to make a web application in Java with a login/session system using com.sun.net.httpserver and as far I know, it does not have an inbuilt method to this. So, I had the following idea: 1 - ...
1
vote
3answers
152 views

Hidding ip address in a peer to peer connection

I'm curious is it possible to hide the ip address in a peer to peer connection. Mainly considering you have 2 computer connected remotly in a browser session. I would like to know if it's possible to ...
6
votes
3answers
1k views

What's wrong with my own authentication scheme?

So I want to write my own authentication scheme for a web-app server, as follows. I assume this is a Bad Idea from either security or cost-effectiveness reasons and I know the conventional wisdom is ...
2
votes
2answers
214 views

Would usage of jCryption 3.0 + SSL have mitigated the Heartbleed vulnerability?

I came across a project called jCryption 3.0, which encrypts data between the client and server, without using SSL. If a website's JavaScript had used jCryption 3.0 to encrypt login form fields before ...
2
votes
2answers
388 views

Hacked HTML page - what's in the comment following the obfuscated code?

Chrome just warned me about malicious content when visiting a site - so I visited it. The source code is like the following: <html> <head> <link href="images/DPT2.ico" title="Dynamic ...
0
votes
2answers
376 views

SQL Injection and JavaScript Regex Bypass

me for learning SQLI. But I got stuck at this one regex which seems to be unbreakable : document.loginForm.username.value = document.loginForm.username.value.replace(/[^a-zA-Z0-9]/g, ""); If someone ...
0
votes
3answers
166 views

Does this reflected XSS vulnerability pose any real threat?

I have a web site where users can enter some text into a textbox and that text is immediately rendered in a div using javascript (strictly front end). If a user enders something like this: This is ...
2
votes
1answer
111 views

user data accessible through javascript in browser

There are websites which display user information, such as browser version and operating system This website goes even further, and displays some additional information, such as desktop resolution, ...
2
votes
3answers
199 views

hiding javascript in image

I have read a post in thehackernews and searched the net to find how it worked. How can anyone add javascript in an image such that when the image is displayed it can run a script. Can this be done ...
1
vote
1answer
107 views

BeeF - How does it work?

I'm mainly server sided. I haven't worked with JS that much before. My coworker was talking about beef and how it basically controls the victims browser just by a simple xss attack I was wondering ...
2
votes
4answers
248 views

Why aren't we all compromised on the internet?

Well, I've been thinking about this for a while now. Within the last decade, we've used various ways to make our websites look dynamic and live. For example, in JavaScript, it's quite easy to send ...
2
votes
2answers
315 views

Is this password generator safe?

128-bit entropy is required http://nxtra.org/nxt-client/js/passphrasegenerator.js With all new browsers (Chrome, Firefox, IE 11) it uses crypto.getRandomValues which should be safe, but with IE 10 ...
1
vote
1answer
124 views

Review of approach to client-side only hashing and encryption for web application

Background: I have little knowledge of hashing and encryption, so please bear with me. I have posted a related question here: ...
0
votes
1answer
75 views

Sending passwords securly over the net: javascript? [closed]

I believe SSL is decrypted and encrypted from your computer to the receiver right? Well is it possible to use any type of encryption (Stanford crypto lib?) to get a password safely over the net these ...
2
votes
2answers
506 views

Are HTTPOnly Cookies submitted via XmlHTTPRequest with withCredentials=True?

I have a two part question here. I have a javascript webapp accessing privileged REST endpoints. I would like to protect against CSRF. Currently, I have a login system built which returns a login ...
3
votes
1answer
568 views

How to secure my REST implementation for an ember.js app

I've been searching and searching for what seems days and have not come up with any definitive answer on a solution to my problem. To explain without going into terrible detail I am building a store, ...
1
vote
2answers
416 views

Digital Signatures of XML, PDF and Office Documents on every platform

I'm trying to develop a website that performs digital signatures on client-side and then sent the signed document to the server-side. I want to do the signatures on client, due to the fact of not ...
1
vote
1answer
754 views

File upload vulnerability

I am trying to pentest a webapp challenge. Is the following control code vulnerable to file upload? I would like to upload a php shell... I am able to upload shell.php.jpg file but I receive the ...
1
vote
3answers
133 views

Authorization with MD5 imlemented in Javascript

I want to use MD5 function (JavaScript library) to hash password before send it to server during logging in to website and during registration proces. I want to ask is it a secure method? I can't ...
2
votes
2answers
404 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 ...
0
votes
2answers
260 views

JS code vulnerable?

Can you please help me in order to understand what exactly do this code and if it is could be vulernerable? <script type="text/javascript"> function getUrlVars(){ var vars ...
1
vote
0answers
97 views

Hacking attempts:in.js

A client of mine keeps getting hacked by seemingly SQL injection where a script tag containing a link to an "in.js" file is added. Sometimes from a domain called sportserve.co.uk, other times from ...
1
vote
2answers
969 views

Possible attack on website

I am a developer and I therefor I have very little knowledge on security. So I need some help understanding the attack on website which we launched recently for one of our client. Website is built on ...
0
votes
1answer
510 views

exploit document.write with unsanitized user input

I'm trying to inject javascript into a js scriptfile but it's not working. I have the following setup: html file with javascript-file include (all inline js is blocked!) Welcome, <script ...
0
votes
1answer
170 views

Is it html escape enough for mitigating all xss, if html is going to be generated only in client side?

If all html in a site is generated in client side (attributes, urls, styles everything will be concatenated in javascript and set as innerHTML), is it doing only html escape enough for mitigating all ...
1
vote
2answers
1k views

Is jQuery.val() enough to prevent XSS

Is obtaining the value of a textarea/input with the jQuery function .val() XSS-proof? <html> <textarea id="t1"></textarea> <script> var toBeDisplayed = ...
1
vote
1answer
79 views

What is the best approach for securing log-in credentials on an HTML form?

I realize how basic this question is, but I have relied for years on mechanisms built into .NET to handle log in for me. These days, most of my work involves using client-side logic and calling API ...
0
votes
2answers
237 views

Is it possible to modify a support .js file in a web application by injection?

Let's say there is a web application needing a JavaScript support file .js to be loaded in the head of the html document. <!DOCTYPE html> <html> <head> <meta ...
3
votes
1answer
578 views

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. ...
2
votes
0answers
726 views

AngularJS Static Analysis Tools [closed]

I am setting up a software security initiative at a small software company. Part of this is selecting a static analysis tool for early and automated detection of security vulnerabilities. Many ...
4
votes
1answer
197 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: ...