When analyzing the IIS Logs, sometimes the csUserName field comes in form of a code, such as lDU9TNFo9/IwGz75KGQn5YB4KJlsX+UamJx11y4M2muiWSWyXCE6vbeQgG1kHXxG
I thought it could be base64 encoding, but I couldn't decode using online tools.
I know the csUserName may point to the user of the web application, I know this may be the SID of a user and sometimes may be the SID of system user accounts, but how to decipher this code?
cs-username means the name of the authenticated user that accessed the server. Anonymous users are indicated by a hyphen. So your csUserName field may be that the user is not authenticated.
Related
If you log into a platform (Twitch, Blizzard, Steam, Most Crypto exchanges, Most Banks) from a new device you'll typically get an email stating so.
As far as my knowledge goes, the only information you can get on a request is
IP address
Device Operating system & version
Browser type & version
Are these platforms basing their "unique" users off of this information alone and/or am is there more information that can be gathered?
From a security perspective the largest thing is your identity or how you authenticate. That's king. The email stating "hey this is a new device" I've seen handled differently from site to site. Most commonly it's actually browser cache and I see banks specifically use browser cache to store these kinds of tokens. Otherwise every time your cellphone connected to a new cell tower you'd likely be flagged as different. They're not necessarily the same as an authentication token, rather it just says hey I've authenticated as this user to this site before. Since it's generated by the service provider, the service provider knows to trust it, and it's nearly impossible to hack (assuming it's implemented correctly).
From my own experience the operating systems and browser types, that's more record keeping than actionable insights, however you could build a security system that takes into account an IP address from very different geo-locations. I.e. why is this guy from the US logging in from China. They just logged in from California 3 hours ago, this is impossible. I don't believe most sites really go to that extent though. I do see MFA providers saying "hey there's a login from china, do you want to approve?". That workflow makes a lot more sense.
The last part of your question is tricky, regarding "unique users." Most calculate that based off the number of sessions opened (tabs), or in the case of Twitch (since you mentioned them specifically), the number of tabs that are streaming that video in. These open platforms where anyone without an account can stream the content obviously treat this differently than say Netflix that makes you authenticate and each account has a limited number of sessions that can be open.
AFAIK, most of the systems like this stores a cookie in your browser when you log (not the session cookie, just a random ID) that is also assiciated to your account in the provider database, so when you came back, you log in, and they check whether you have that cookie set and in case if the ID matches
They you can probably do some more advance stuff with that ID, like base that value from the browser, OS, expire date and so on
I'm trying to implement a GET method with Express in my nodeJs application.
I'd like to do something like this in order to display user data :
router.get("/user/:idUser", (req, res) => {
The user doesn't need to be authenticated in order to execute this code. However I don't want that anybody can execute this request with a user id of someone else. Because he could see data he's not supposed to see.
How could I proceed ? I thought about using some encryption process to have something like :
/user/PdfgdfJFDGTfrfgdsf
Your question isn't really making sense. You don't want authentication, but you only want a user to be able to view their own data so nobody else can view it.
The ONLY way to solve that is by using some form of authentication. The user has to prove to the server that they are allowed to view that data before the user renders the page for them.
Yes, you could obscure the URL (make it some mostly unguessable string of characters), but it's not clear what problem that is solving. The user themselves won't be able to remember it or type it so it would probably have to be a link in a web page and if it's a link in an unauthenticated web page, then anyone can get to it - thus defeating the purpose.
There are cases where temporary links (often done for privileged downloads) such as what you mention /user/PdfgdfJFDGTfrfgdsf are sent via an authenticated channel (either an authenticated webpage or sent to an email address known to belong to an authenticated user) and these links contain some unique and hard to guess code. The user can then click on that link (in authenticated webpage or in email) and access that resource without further authentication. In that case, the knowledge of the code in the URL is serving as a form of proof of authentication. Because URLs may be logged in service providers or corporate infrastructure and thus not remain entirely private, this technique has its limitations and is typically only used for short term (download this resource in the next 10 minutes) type of uses, not a long term substitute for authentication and not used for things that demand real security. You don't explain enough of your use case to know whether this is practical for your situation or not.
The user doesn't need to be authenticated in order to execute this code. However I don't want that anybody can execute this request with a user id of someone else. Because he could see data he's not supposed to see.
That's an inconsistent statement. You say "user doesn't need to be authenticated in order to execute this code" and then you say "I don't want that anybody can execute this request with a user id of someone else.". You can't have both. The user is either required to prove authorization or they aren't. Pick one. It can't be both.
you can use jwt for this and a auth middleware for this
upon decoding jwt token, you can implement logic to check if the decodedToken.user_id (given that you add user_id when encode token payload) is equal to the :idUser in route (or any kind of logic you want) there.
Hello fellow developers
I have obviously under estimated a thing when developing my first complex web site, where user creation and login is required.
It appears that cookies can be edited and modified by the user logged in, by using some developer tools i.e. in Google Chrome. That, I never gave a thought.
So, here is my issue.
When the user is logged in, I store the user name in a cookie.
If username-cookie is not blank, and I can find a user file with that name, the user is logged in, per se. Otherwise, no user is logged in.
When the user logs out, I simply expires the cookie, which works fine.
Now, the problem is, that a user obviously can edit the content of a cookie, outside the web application, or with javascript.
What would be the correct approach here to ensure, that the username cookie is not compromised in any way, other by my web application?
Making them read-only is not possible, I assume. Encrypting the cookie and then decrypting might work, I guess. Then, the cookie would be nonsense to the user, and if modified, result in a logout, as no valid username can be found upon decrypting the edited cookie.
I have stalked Googles cookies, and it appears that there are a lot of xxID cookies, which contains garbage. Does that mean, that encrypting/decrypting is the only way to make it work? I also considered some kind of login-ticket, but that would require a table lookup every time a user interacts with my web page.
Can anyone give me a hint as to what would be the correct approach?
Thanks in advance
Best regards,
Karsten Heitmann
You should look up session management for the language you are using.
The traditional approach is that when a user logs on, your application generates a long, cryptographically random token called the "session id" and sets that into a cookie. It stores data like who is logged in on the server side identified by the random value, so when a logged on user comes back, the browser sends the cookie with the random session id and the application can look up session data on the server side. This way an attacker has no way to guess a valid session id for a logged on user, assuming the session id is cryptographically random and long enough (which more precisely means it has enough entropy). Logging out means deleting the session data on the server side, and also removing the cookie, but that is not the most important part - the session will be invalid anyway.
Note that you should not code this yourself. You did not mention the language and environment you are developing in, but session management is rather tricky business if you want to secure it, and it is already provided by most languages / frameworks.
Just for curiosity, the encryption approach you mention is by the way a valid one. Some frameworks actually do that, but you should not attempt to code that either, because it is very easy to get it wrong, lots of things need to be taken care of to make it secure enough. Unfortunately an answer here is not the right format to go into details I'm afraid.
Btw you mention looking at Google. They use their own single sign-on solution, it is very complex compared to simple session management, so it's probably not the best example for you to look at. Find simple websites, most of those work the traditional way.
I'm writing a GWT application where users login and interact with their profile. I understand that each form entry needs to be validated on the server, however, I am unsure about potential security issues once the user has logged in.
Let me explain. My application (the relevant parts) works as follows:
1 - user enters email/pass
2 - this info is sent back to the server, a DB is queried, passwords are checked (which are salted and hashed)
3. if the passwords match the profile associated w/ the email, this is considered success
Now I am unsure whether or not it is safe to pass the profile ID back to the client, which would then be used to query the DB for information relevant to the user to be displayed on the profile page.
Is there a possibility for a potential user to manually provide this profile ID and load a profile that way? My concern is that somebody w/ bad intentions could, if they knew the format of the profile ID, load an arbitrary amount of information from my DB without providing credentials.
-Nick
What you are dealing with here is a session management issue. Ideally, you want a way to keep track of logged in users (using random values as the session key), know how long they have been idle, be able to extend sessions as the user is using the site, and expire sessions.
Simply passing the profile ID to the client, and relying on it to send it back for each request is not sufficient - you are correct with your concern.
You want to keep a list of sessions with expiration times in a database. Every time an action is executed that needs user permissions (which should be pretty much everything), check to see if the session is still valid, if it is, extend it by however long you want. If it is expired, kill the session completely and log the user out.
You can store your session keys in a cookie (you have to trust the client at some point), but make sure they are non-deterministic and have a very large keyspace so it cannot be brute forced to get a valid session.
Since you're logging a user in, you must be using a backend that supports sessions (PHP, .Net, JAVA, etc), as Stefan H. said. That means that you shouldn't keep any ids on your client side, since a simple id substitution might grant me full access to another user's account (depending on what functionality you expose on your client, of course).
Any server request to get sensitive info (or for any admin actions) for the logged in user should look something like getMyCreditCard(), setMyCreditCard(), etc (note that no unique ids are passed in).
Is there a possibility for a potential user to manually provide this profile ID and load a profile that way? My concern is that somebody w/ bad intentions could, if they knew the format of the profile ID, load an arbitrary amount of information from my DB without providing credentials.
Stefan H is correct that you can solve this via session management if your session keys are unguessable and unfixable.
Another way to solve it is to use crypto-primitives to prevent tampering with the ID.
For example, you can store a private key on your server and use it to sign the profile ID. On subsequent requests, your server can trust the profile ID if it passes the signature check.
Rule 1 - Avoid cooking up your own security solution and use existing tested approaches.
Rule 2 - If your server side is java then you should be thinking along the lines of jsessionid. Spring Security will give you a good starting point to manage session ids with additional security features. There will be similar existing frameworks across php too (i did not see server side language tags in the question).
Rule 3 - With GWT you come across javascript based security issues with Google Team documents and suggests XSRF and XSS security prevention steps. Reference - https://developers.google.com/web-toolkit/articles/security_for_gwt_applications
I'm in the process of using the facebook javascript sdk to provide user login functionality for a website.
What I'd like to do is simply take the logged in user's unique facebook id and then put/fetch data to/from a mysql database using the id to determine what data is available to said user.
However I don't really feel like this is very secure. Whilst I'm not storing anything sensitive like credit-card details etc, I'd obviously prefer it to be as secure as practically possible.
My fear is that with javascript being what is it, someone could fake the facebook id and just pull whatever they wanted.
I'm aware that the php sdk would provide a solid solution to this problem, but i like the javascript one mainly because it's easy to use and I have the basis of it set up (I admit it, I'm lazy).
So, my questions are:
Would this set up be as insecure as I feel it might be?
Is there anything I can do to improve the security of such a system, other than switching to the php sdk?
Thanks!
Facebook Ids are pretty hard to make up (at most a user will only know their own). Depending on what you store in the database (which will not be anything that the user cannot get on their own, unless you ask for extended permissions)
If you are worried about a user trying to get information from the database, add an access token or signed request to each row and us that and facebook id to get data. That will greatly increase security.
EDIT
There are few occasions where you get a signed request from a user:
* A signed_request is passed to Apps on Facebook.com when they are loaded into the Facebook environment
* A signed_request is passed to any app that has registered an Deauthorized Callback in the Developer App whenever a given user removes the app using the App Dashboard
* A signed_request is passed to apps that use the Registration Plugin whenever a user successfully registers with their app
Signed requests will contain a user id only if the use has accepted permissions though, and are not passed again if the user enters the application, and accepts permissions (meaning that the signed request would not contain the ID). Because of this saving an access token may be a better idea. Here is more on the signed request
Also the signed request is in the url (param = "signed_request"). I always parse it through c# but I am sure you can at least get one through javascript
It's pretty easy to spoof the origin using curl. I'd imagine Facebook has another mecanism in place to make this possible. If you inspect their code, it appears that they generate an iframe and pass requests through. If I had to guess, they have setup the requests to only be made from the Facebook domain, and ensure that the iframe can only be embedded in a page that has a white listed domain.