Cross-Site Scripting: An attack method that involves injection of code or markup into a webpage. There are three major types of XSS: Reflected XSS, Stored XSS (aka persistent XSS) and DOM-based XSS (aka client side XSS).

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Is always using HTTPS a good idea? [duplicate]

OK, this question might seem a no-brainer for a professional but keep in mind I am not a professional web developer so my knowledge in this field is very limited. I have been pondering over time ...
2
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1answer
370 views

302 redirect and the body on the page (you are redirected to …)

I have page which take URL on query and string and it. Then, you get redirected using 302 to another page, and the response of the page contains HTML code and the redirect header. Like this: <html&...
1
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1answer
120 views

Is it possible to get a flash src after a redirect or an element inside an embed/object/iframe tag (cross-domain)?

The URL example.com/auth will automatically redirect the user (HTTP 302) to example.com/signed_in.SWF?token=SENSITIVE. Is it possible for an attacker to steal the token, using javascript or flash, in ...
0
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2answers
121 views

Reflected XSS quote not encoded

I am attempting to exploit URL with a reflected XSS as follows: http://domain.com/vuln_parm= The contents of vuln_parm gets returned to the user as follows: <div attrib1="" attrib2="" ...
2
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1answer
76 views

How dangerous is reflected request query strings?

I have discovered a possible security flaw in a login for a site that many people rely on. I won't say the site but in the URL there is something similar to /Success?message=Success+please+wait+a+bit+...
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1answer
73 views

Why my XSS attack's onerror method not firing?

I have been able to inject an onerror event to the HTML. In the image you can see onerror has been injected, but it never fires.
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2answers
2k views

How to launch XSS code from an INPUT HTML tag upon page load?

Say I have the a website with the following code on it: <input type="text" id="search-text" name="query" value="?" /> Double quotes aren't escaped so I can break out of the value attribute, ...
5
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2answers
228 views

Dangers of XSS on the server-side vs client-side

I was looking here, and I understand that reflected-DOM XSS(Client-side XSS) does not go through a server-side script but Reflected XSS (Server-side XSS) does, but neither hits/gets stored in the ...
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1answer
637 views

Token contains a reflected XSS vector in the <form > tag error in Chrome

We have a web app and we send the back URL through post to various pages to enable users come back to the parent. The double quotes are translated to &quot; to avoid XSS and then translated back. ...
3
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1answer
729 views

Does a Content-Type: text/plain header protect against XSS in browsers?

I'm creating a small web script that mostly redirects the browser but has some error conditions when input parameters cannot be validated. I'd like to display error messages like parameter XXX had ...
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3answers
1k views

In NodeJS, what is a good way of ensuring user submitted data in (text input) forms is not malicious?

In addition to scanning user uploaded files, I would also like to ensure that forms for user profiles, comments, etc. cannot be misused to submit malicious script. What are some known good methods of ...
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1answer
47 views

Is XSS possible if I insert untrusted data into an quoted HTML attribute and HTML encode the " sign?

If I insert untrusted data in a HTML attribute like this: <img src="http://www.mydomain/<%untrusted_data%>"> and if I HTML encode the " sign in the untrusted data, is this particular ...
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4answers
1k views

XSS for stealing cookies … not anymore?

The other day I found a XSS vulnerability in a website that a friend told me to Pentest. It was a page from a school that he's managing, so the important thing here is the login credentials == COOKIES....
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2answers
461 views

http_only for cookies with JWT tokens

I'm trying to figure out how to use JWTs that are transmitted in cookies for an SPA It needs to be in cookies because we want non-ajax requests to also send the jwt, and it should "just work" for all ...
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0answers
91 views

XSSF cookie stealer not working

I am playing with XSSF with Metasploit and attacking Mutilldae(security 0). I was able to get the generic XSS inject working. The inject was added to the Mutilldae blog. However, when I try to get the ...
2
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1answer
171 views

Reflected XSS via $_FILES

Is it possible to perform a reflected XSS attack via the $_FILES variable? The vulnerable code I am imagining might look like this: echo $_FILES["file"]["name"]; I read that it's not possible to ...
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2answers
151 views

Persistent XSS in Blogger domain

I have discovered persistent XSS in blogger domain. I have reported vulnerability to Google Security Team and I received this is the response: Users are permitted to place arbitrary JavaScript, ...
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3answers
305 views

Is this code javascript vulnerable to DOM based XSS?

Code : <script> document.theform.reference.onchange = function(){ var id = document.theform.reference.selectedIndex; var url = document.theform.reference[id].value; ...
3
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4answers
764 views

Famous XSS attacks over JavaScript [closed]

I'm about to graduate in "Computer Science", and I'm writing thesis about the Javascript vulnerabilities. In particular, I'm analyzing the JS vulnerabilities that allow XSS attacks. I would like to ...
2
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1answer
423 views

XSS in Content-Disposition

Lets assume i have found a xss on site example.com, now to trigger an XSS, i use the following URL: https://example.com/a.php?v=%22%3E%3Cimg%20src=x Which results in following response: HTTP/1.1 ...
3
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1answer
537 views

Content-Security-Policy data: scheme

I have a Cordova app that transforms some images to base64. This violates CSP with this message: Refused to load the image 'data:image/svg+xml;charset=US-ASCII,%3C%3Fxml%20version%3D%221.0%22%...
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0answers
175 views

Tools for finding stored XSS vulnerabilities, given DB write access? [closed]

I'm aware that there are various tools for testing for XSS vulnerabilities. However, all the ones that I'm aware of (Vega, possibly BeEF, etc.) operate purely client-side. When testing for stored XSS ...
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1answer
92 views

What kind of attacks do Javascript WebWorkers protect against?

What kind of attack are prevented by running code submitted by the user in a Javascript Web Worker? Do they prevent attacks like XSS, or is it better to use some other sandboxing method to protect ...
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3answers
871 views

What are the different payloads used for XSS vulnerability? [closed]

I am new to information security field. I am searching for XSS vulnerabilities. In XSS mostly they use <script>alert('XSS')</script> payload for attacking a websites. In the case of ...
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1answer
505 views

XSS payload to capture login credentials

I am trying to solve this exercise http://pentesteracademylab.appspot.com/lab/webapp/jfp/3. The objective of this is to "Post the Username and Password to Attacker Controlled Server". There is a url ...
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0answers
62 views

XSS only works when GET request is submitted with form [duplicate]

I'm trying to create a POC for responsible disclosure, but I'm having an issue... When I use a textbox to submit my payload, it brings me to another page where the javascript executes and is present ...
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1answer
106 views

Any standard tests to prevent hacking? [closed]

I am very new in programming world so my question may sound weird. I am useing selenium to test an application, yesterday one of my colleagues found this issue that if someone enters this: <script ...
2
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4answers
471 views

Is it possible to exploit unescaped user input into JavaScript form which only gets data via AJAX request?

A logged in user can get to a page https://example.com/some/page which has an input field and some buttons. When user enters something into this field and clicks away on anything, the page makes ...
0
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1answer
16 views

Security risks for a simple network configuration screen in android [closed]

I am building an Android App that pulls chart information from a server where the connection is specified on this view Ideally, the end user will put in a valid host and port resulting in business ...
3
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1answer
127 views

Possible issues when one or more cookie not HttpOnly

I have a question related to HttpOnly cookie. Tracking other threads wasn't of much help, hence I am posting my query here to learn if you can foresee any issues with my understanding. There is a ...
3
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1answer
552 views

Dom based Xss Query - location.hash

I was just looking at Dom based xss and wondering if hash value is written to a variable in javascript context can lead to Cross site scripting. The code looks something like this: <script> var ...
2
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6answers
134 views

Close XSS vulnerability

I run a vulnerability scanner on my website which showed me a couple of vulnerabilities which look like this: http://.../search?text=&ClassIDNames[37]=<script>alert('Found')</script>&...
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4answers
2k 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
199 views

Security implications of providing users subdomains on my domain?

I want to provide users with sub domains on my website. Users will provide an ip address and the sub domain they want and I will then use a DNS service to redirect to that IP through an A record or ...
2
votes
2answers
447 views

What do I do if I find XSS on my website?

I found reflected XSS on my website. And its fixed now. There are a lot of websites which tell how a XSS can be detected or what can be compromised but I could not find what measures should be taken ...
4
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1answer
85 views

Practical implications of 2014's android SOP vulnerability

For a project at university I have done research about all kinds of security issues, especially privacy-related ones, that have come up on mobile OS and applications over the last few years. One of ...
5
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2answers
2k views

Are phone apps vulnerable to XSS or CSRF? (Webview, Phonegap, chrometab)

I need to provide evidence that CSRF or XSS is possible on a phone... using PhoneGap, a Webview, or specifically a "Chrome Tab" or iOS equivalent. I believe in theory this is possible, and mitigation ...
3
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3answers
267 views

Any Security Risks for using mailto:?

I use a PHP script which performs a database search and when no result are found, user is presented with a mailto link with this format mailto:example@test.com?subject=SEARCHED_QUERY_HERE The ...
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1answer
140 views

Is this reflected or DOM-based XSS?

Scenario: Server-side script takes URL parameter parameter1 and writes it without encoding into cookie cookie1. Then regular HTML page containing client-side script is returned. Client-side script, ...
2
votes
1answer
167 views

REST API - XSS prevention - When and how?

I am currently developing a REST API with Java EE and MySQL, it will feed Data to a Android App. The Data comes from an AngularJS Frontend. So my questions are, when: When do I escape the data? Before ...
0
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1answer
1k views

What makes an Android application vulnerable to Cross-site scripting (XSS)?

Definition of XSS If you search the web, there are many different ways to define a cross site scripting attack. Simply put, XSS vulnerabilities occur when a malicious attacker is permitted to inject ...
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vote
1answer
591 views

Preventing reflected XSS in URL [duplicate]

We have just had some pen testing completed against a web application and the one area identified as High Impact and Medium Probability was: Cross-Site scripting (reflected) The example given was ...
2
votes
1answer
125 views

Concerns discussing 'illegal' activities in a job interview [closed]

Before I begin, I say 'illegal' because I guess the law is somewhat sketchy around the topic and that topic is XSS research. Apparently people have been taken to court over it and UK law does have a ...
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2answers
662 views

Security issues on allowing Special characters in input field

I am building a web application, in which I am required to let user enter any character(even special characters - ~!@#$%^&*()_-+=|\{}[];:'"<,.>) in an input field. To mitigate the problems ...
4
votes
1answer
571 views

Exploitation of Reflected XSS on Android App

I am trying to do a security evaluation of an android application. I came across a situation where one of the activities of the app displays certain form fields in a webview. This form is very ...
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votes
1answer
90 views

Could blocking script in the url prevent DOM XSS? [closed]

On my site, if I were to block <script> from the url, could this prevent some cases of XSS? Any way someone could bypass that?
6
votes
1answer
314 views

How do I securely embed an <img> tag using a user-given URL?

If I hypothetically wanted to allow users to use an avatar from an arbitrary URL like this: <img class="avatar" src="{user input}" /> There are many problems that I can think of: There are ...
4
votes
2answers
106 views

Why do ID attributes need stricter validation?

According to OWASP XSS Prevention Cheat Sheet, one should Strictly validate unsafe attributes such as background, id and name I understand that background could contain data: urls, and can ...
7
votes
1answer
362 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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1answer
3k views

How to exploit CRLF Injection?

I was running a few tests on a website when I came across this: Request: GET /accounts?intended_destination=internal_api%2Fcampaigns_dashboard%7Cshow&intended_params=format%3Dhtml HTTP/1.1 Host:...