An application that is accessed over a network such as the Internet or an intranet using a browser.

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487 views

Should I ask a user to re-authenticate if the browser thumbprint changes? Is a server side library available?

Is there a security benefit to using the browser's thumbprint in addition to a session identifier to identify a unique session? Would it then be advisable to ask the user to reauthenticate (or simply ...
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2answers
5k views

What can an attacker do with a stolen SSL private key? What should the web admin do?

What can an attacker do with a stolen website certificate and key? What should the website admin do upon learning this?
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2answers
1k views

What are the SQL-injections issues of parameterized queries?

I've written some code to generate an SQL query in ASP classic. I'm not sure if it's secure or not: Set adoCon = Server.CreateObject("ADODB.Connection") adoCon.Open "Provider=Microsoft.Jet.OLEDB.4.0; ...
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3answers
3k views

What is the next step of this file upload attack?

Yesterday I discovered somebody had uploaded this PHP code to my server as a .jpg file via my asp.net MVC application's "Upload your profile picture" form. I believe the attack was unsuccessful for a ...
10
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4answers
2k views

Is there a typical step-by-step A-Z process for testing a Web site for possible exploits?

I'm interested less in the tools of the trade (there are many questions here already about that), and I am interested more in the process by which you would go about using those tools. So for ...
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2answers
665 views

Recent Facebook XSS exploit details

There was a recent XSS exploit on Facebook that posted a vulgar message and got users to click on a link to spread the payload. What vulnerability was exploited, and what can other sites do to avoid a ...
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5answers
4k views

Does setting httponly prevent stealing a session using XSS?

If a session token is stored in a cookie that has httponly set, is there any way that a XSS vulnerability could allow a malicious user to steal a users session token?
10
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3answers
701 views

What security features should be present in every web-based CMS?

What are the most important security features that a web-based CMS should offer? What's vital? What would be nice to have? What features should the CMS not attempt to do? Please note: I'm looking ...
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4answers
390 views

What are the drawbacks of login request throttling?

In a web application, one way to protect against password guessing attacks is to lock out accounts after a set number of failed logins. This could be done on both source IP address and username. For ...
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3answers
909 views

If I am obliged to store a password/certificate on a client side, how can i make sure that it is protected?

In certain cases we need to establish a key/password/certificate as a first timer and then as a client we need to use this key/password/certificate to get authenticated. Therefore the ...
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4answers
8k views

Is client side encryption really better than server side?

Web application may encrypt all user data at client side to convince users that it can't decrypt them. When user enters password, it's used to encrypt data in browser and then it's sent to server in ...
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1answer
403 views

Is there a web application firewall equivalent of virustotal?

I'm wondering if there is a web application firewall (WAF) equivalent of VirusTotal? A site where I can throw for example injection strings, exploits or xss, and it will tell me what the default ...
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2answers
3k views

How to protect against clickjacking attack but allow legit iframes?

I'm aware of modern anti-clickjacking approaches, such as X-Frame-Options header or framekiller scripts. But all these tactics prevent content to be inside iframe. But what if there is a requirement ...
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3answers
2k views

How to perform penetration testing on a Flex application?

Possible Duplicate: What tools are there to inspect Flash SWF files? I have decompiled it, verified the source. All seems fine. Appscan also is not able to find anything in this case. But I ...
10
votes
1answer
914 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 ...
9
votes
6answers
2k views

when is it safe to click through an SSL warning message?

How does a user know if it's safe to click through scary browser warnings about SSL certificates? Ideally, a user should never need to click through these warning messages, but sometimes honest ...
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5answers
3k views

How does CAPTCHA mitigate DDoS attacks?

This seems like an easy question, but I've failed to find an answer. One of the uses of CAPTCHA is to cope mitigate Denial of Service attacks. Suppose an adversary performs excessive login attempts, ...
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votes
7answers
401 views

Aren't permanantly logged in accounts inherently insecure?

The basic premise behind a "keep me logged in until I log out" feature is a cookie is stored with some identifier that is used to log the user in again when returning to the site. While these ...
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votes
3answers
23k views

Is there any SQL injection for this PHP login example?

I want to write a login form, and I got one example from the web. I want to know, if there is any SQL injection for this code? If there is, what could the exploit's web form entry look like? This is ...
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3answers
3k views

Is it possible to forge a post request?

Consider the following URL http://mysite.com/form?date=x. Suppose that if x is in an incorrect format, that a page is returned with <p>x is not a valid date</p>, where the page author has ...
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2answers
2k views

When viewing my website from port 3306, I see some weird MySQL info

If I visit my web URL and force port 3306 (MySQL), I see a suspicious looking web page: Is this exposing any vulnerabilities for me? Should I block port 3306?
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3answers
1k views

How do I secure my SaaS startup?

I came across this question I like to offer my startup also for security advice. Objective: building a SaaS web application that allows businesses to quickly open up online stores akin to Yahoo! ...
9
votes
4answers
340 views

What are the main security considerations that must be taken into account if you intend on creating a (localised) whistleblower website?

Also: Is it something that can be achieved with limited funds? I ask because I am intrigued by the obstacles that are in place.
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2answers
962 views

Should user be allowed to save password in browser?

The auditing company found a bug "The Auto-complete form attribute is set in password field". They suggested to disable autocomplete for this field to prevent disclosure of it "when working on shared ...
9
votes
3answers
4k views

Is there a way to bypass Django's XSS escaping with “unicode”?

Django (the Python web framework) escapes output to prevent XSS (Cross Site Scripting) attacks. It replaces ', ", <, >, & with their HTML safe versions. However this presentation on slide ...
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2answers
589 views

Is allowing unfiltered curl request from a website a vulnerability?

Recently I was on a website which provided some non-sense feature: Enter a URL Press enter HTML source of a given URL is displayed It basically fetched a URL and just dumped the contents of it. ...
9
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1answer
8k views

Why is it so hard to close onion domains (e.g. The Silkroad)?

A few months ago when I started to experiment with bitcoin I came across The Silkroad (only accessible via Tor) For those who do not know what Tor is and who do not want to waste their time ...
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2answers
2k views

Security Concerns on clientside(Javascript)

We are going to design and implement a UI for a big website. Owner of the site is really cautious about security issues. I wonder if there is a check list for security issues at the client-side ,while ...
9
votes
1answer
692 views

XSS Technique - & JavaScript Include

I was looking through the OWASP XSS Filter Evasion Cheat Sheet, and there was one technique that was completely new to me: & JavaScript includes <BR SIZE="&{alert('XSS')}"> I ...
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2answers
987 views

Isolating Web application hosted on same web server

I am working on a scenario if we have two or more web application hosted on a same server. Let says Web application X is vulnerable so how can i be sure that it will not effect the other web ...
9
votes
2answers
330 views

Is there any risk related to allow user to give an URL as their image profile?

Building a website, I'd like to allow users to specify an url that point to an image that will be used as a profile picture (included in the HTML DOM as a ). But before doing anything stupid, I was ...
9
votes
4answers
830 views

Worthwhile from security standpoint to limit database server user for ASP.NET website to only EXECUTE on stored procedures?

I know that obviously we must avoid sql injection attacks through user input validation and parametrized queries. There's already a firewall in place on the database server to limit remote ...
9
votes
4answers
360 views

Defending site against being abused by phishing

Say you have a web site and you are using some returnUrl URL parameter to redirect user back to page where he was after login or editing some records in user area. Is there some standard way how to ...
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4answers
1k views

Preventing insecure webapp on subdomain compromise security of main webapp

I want your help on getting more concrete information on a type of vulnerability that I remember vaguely. I vaguely remember hearing about a year ago that if you set up a webapp on a subdomain, and ...
9
votes
2answers
4k views

Is doing credit card transaction via 3G secure?

3G, GPRS or other mobile-based connection. Because it seems like it's easier to intercept, than, say, land-based connection or encrypted WiFi. If it matters, the transaction I want to perform is ...
9
votes
3answers
2k views

Encrypting user data using password and forgot my password

I am planning to do a web application which stores a lot of personal stuff (info, photos...). And to give users a sense of protection, I want to encrypt the data before storing it to the database. ...
9
votes
3answers
1k views

AES using derived keys / IVs. Does it introduce a weakness?

I'm looking for an efficient way to encrypt multiple fields in a database with AES using a single global key, used throughout a large web application. Obviously in order to re-use this key, a unique ...
9
votes
3answers
1k views

localStorage for apps over https. What expectations are there?

I run an online gradebook. To keep student data private, I transfer all data over https. Now, I'd like to use localStorage to avoid redundant calculations and server requests. However, according to ...
9
votes
2answers
795 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 ...
9
votes
3answers
7k views

CSRF cookie vs session based tokens

I will generate a CSRF token and include it in a hidden form field. When receiving the request, I will check the form value against the value either stored in the user's session or in a cookie. Is it ...
9
votes
2answers
822 views

Security issues with PHP Sandbox

I am working on a PHP sandbox for a Web Application Honeypot. The PHP sandbox will analyze a PHP file that may have been injected as part of an RFI attack. It should run the file in a safe environment ...
9
votes
2answers
6k views

Keeping user session alive - security considerations

We have recently developed some functionality for our web app to allow a user to remain logged in indefinitely, and are interested in knowing the security ramifications of doing so. The goal of this ...
9
votes
1answer
1k views

How to make SQL injection in PostgreSQL's tsquery?

I think there is SQL injection vulnerability in an application I'm testing. This is seen when I enter malformed parameters into a search form. All exceptions are shown in format: PHP raised unknown ...
9
votes
1answer
2k views

Does it make sense to implement OAuth when no 3rd party is involved

I own a REST API at server side and a distinct web application that would call those APIs. I want to secure my APIs calls. After some reading, I want to implement the OAuth 1.0a mechanism at server ...
8
votes
5answers
13k 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 ...
8
votes
4answers
1k views

Can I replace username and password with a long random text in URL? [duplicate]

Scenario One customer is facing a problem with his users: they use a (web) service a few times per year and they forget their credentials very often. There is a standard password recovery procedure ...
8
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3answers
2k views

How serious are XSS attacks

A website I visit allows this kind of attack, to be implemented with GET in the URL <SCRIPT SRC=http://ha.ckers.org/xss.js></SCRIPT> Along with many others on this page: ...
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5answers
627 views

How do small businesses handle web app security?

Everything on Owasp's top 10 list, how do current small businesses (< 1000 employees) handle web application security, along with mobile security of their applications? Do they care about info/app ...
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4answers
2k views

Can anti-CSRF token prevent bruteforce attack?

I am not much experienced with brute force attacks but I was wondering Suppose, you have a website www.example.com and you want to do brute force attack on that login form but that login form is ...
8
votes
3answers
742 views

How does an attacker approach a website?

What is a typical mindset and method of approach? What are they likely to try first? At what point does a novice give up versus an expert? How would an automated attack differ from a manual one?