Im concerned an IIS admin user might accidentally press generate key causing the machine key in web.config to be overwritten.
Are people not so concerned, because you just get it from a back up ?
Or does everyone have solid admin processes or good admins dont do that?
I was on a dev Machine in IIS and just pressed the button on the WRONG site.
Test users hosed until machine key restored from backup..
Im now wondering if I should have a customer web.config attribute ?
What is good management practice here?
Any other words of wisdom? Other than im an IIS admin Donk.
Is there some normal way of indicating key in use, cant be/ dont regenerate ?
As far as I know - no. After a bit of research still no.
When dealing with multiple machine keys, a good practice would be to keep them all manually generated in a shared admin resource (spreadsheet, txt doc, etc). In case something goes wrong, restore it from there. As an admin it's your responsibility to keep the keys for certain applications in order if you use these.
Don't worry, mistakes happen. Databases get locked, IIS servers crash etc. All of us admins/developers are still capable of human errors that can't be auto-corrected by tools and features. This is yet just one of them.
Of course the not-so-easy way would be to build your own tool (console/gui) that performs certain validations and use only that to manipulate the keys.
Related
Hi security aware people,
I have recently scanned my application with a tool for static code analysis and one of the high severity findings is a hardcoded username and password for creating a connection:
dm.getConnection(databaseUrl,"server","revres");
Why does the scanner think this is a risk for the application? I can see some downsides such as not being able to change the password easily if it's compromised. Theoretically someone could reverse-engineer the binaries to learn the credentials. But I don't see the advantage of storing the credentials in a config file, where they are easy to locate and read, unless they are encrypted. And if I encrypt them, I will be solving the same problem with the encryption key...
Are there any more risks that I cannot see? Or should I use a completely different approach?
Thank you very much.
A fixed password embedded in the code will be the same for every installation, and accessible by anyone with access to the source code or binary (including the installation media).
A password read from a file can be different for each installation, and known only to those who can read the password file.
Typically, your installer will generate a unique password per site, and write that securely to the file to be read by your application. (By "securely", I mean using O_CREAT|O_EXCL to prevent symlink attacks, and with a correct selection of file location and permissions before anyone else can open it).
This is an interesting one, I can give you examples for a .Net application (as you haven't specified running environment / technologies used). Although my guess is Java? I hope this is still relevant and helps you.
My main advice would be to read this article and go from there: Protecting Connection information - MSDN
Here is a page that describes working with encrypted configuration files here
I've seen this solved both using encrypted configuration files and windows authentication. I think that running your application as a user that will be granted access to the relevant stored procedures etc (as little as possible, e.g. Principle of Least Privilege) and furthermore folder access etc is a good route.
I would recommend using both techniques because then you can give relevant local folder access to the pool for IIS and split out your user access in SQL etc. This also makes for better auditing!
This depends on your application needs though. The main reason to make this configurable via a config file or environmental user account I would say is so that when you come to publish your application to production, your developers do not need access to the production user account information and instead can just work with Local / System test / UAT credentials instead.
And of course they are not stored in plain text in your source control checkin then either, which if you host in a private distributed network like GIT could mean that this could be compromised and a hacker would gain access to the credentials.
I think it depends on how accessible / secure your source code or compiled code is. Developers usually have copies of the code on their dev boxes, which are usually not nearly as secure as production servers, and so are much more easily hacked. Generally, a test user / pw is configured on the dev box, and in production, the "real" pw is stored in much more secure config files. Yes, if someone hacked into the server they could easily get the credentials, but that is much more difficult than getting into a dev box in most cases. But like I said it depends. If there is only one dev, and they have a super secure machine they work with, and the repo for their code is also super secure, then there is no effective difference.
What I do is to ask the credentials to end user initially and then encrypt and store them in a file. This way, I don't know their connection details and passwords as a dev. The key is a hashed binary and I store it by poking ekstra bytes in between. One who wants to crack it should find out the algorithm used, key and vector lengths, their location and the start-end positions of the byte sequence keeping the values. A genius, who would also reverse engineer my code to get all this information would break into it (but it might be easier to directly crack the end user's credentials).
I have a special user, called udpate, whose shell is a special command that fetches any pending updates to our system.
I'd like to be able to open an ssh session with this user without any kind of authentication (password or ppk, or anything), so if anyone wants to update a system, they could do "ssh update#<>", without having to know a password, or have a pre-shared public key on the box.
Insecure, I know, but this is over a VPN, so it should not be a problem, and they will only run the update, and then be thrown out.
Can this be done?
VPN is not a good reason to avoid authentification when using ssh. Even if there is a way to do this, you shouldn't use it. Use a ssh-key is the best way to do it. If you really want to do thing like this, use the same key and distribute it on each box.
What did you do if the local network of your box is compromised ? You just have a security hole.
as this rfc points out, there is support for host based authentication https://www.ietf.org/rfc/rfc4252.txt
So using it carefully should be possible by following this tutorial https://en.wikibooks.org/wiki/OpenSSH/Cookbook/Host-based_Authentication#Server_Configuration_for_host-based_authentication.
That may not be a final solution, but helping finding one.
But really, you should not do it for this usecase... Just offer a basic web endpoint which does only start the update process on the next cron run. I know, its not so "simple" but its a lot more secure.
Or if they have access to this server anyway, add a script with super user bit set which triggers the update.
Also, if you have a central server in your company, where everyone has access too, you can use this as step in between to host the key pair, so you dont need to manage X keys for everyone.
Or you use a more modern setup with puppet or anything, or you just configure the server to always update without user interaction needed....
I know it is possible to encrypt the connection-string stored in the web.config,
And I know you could never be too safe, but since the web.config cannot be viewed or downloaded, why is it needed? in what way is it more secure?
[EDIT:] I'm not using a shared-hosting server.
If you deploy your website to a customer's web server and want to keep the credentials secret.
If someone breaks into your server, he is not able to see all sensitive information without any further work. And if you deploy your application to some "cloud" service your credentials won't be exposed to everyone maintaining the service.
Edit: Also some Administrator or users that have access to the Server won't be able read the clear text credentials.
I think you have answered your own question by saying "you could never be too safe"
The fact that web.config cannot be viewed or downloaded is not a guarantee that an attack from inside your organization could not occur. Someone with the right access could breach the security and get the data if it is visible in plain sight. While as you said, attack via Http is unlikely to get this file, others who have right access could still access through other means such as remote file access, remote desktop, etc. Encrypting + assigning proper access/authorization are making a tad more difficult for the attacker to try to break your system.
In security, you simply have to be paranoid and took every measure you think possible in order to make the data as safe as possible and it's your job giving the attacker a hard time to retrieve any information. I don't think there is such thing as 100% secure. In some sense, you would always be vulnerable to a security threat, all we could do is try to minimize it as much as possible.
Some users are suggesting that my (C#) program should be able to run scripts after completing it's job. This would be done through a command line to be input in my configuration dialog.
I'm no security expert, so I'm not sure if this acceptable in terms of security. Since the app runs with admin privileges (on Windows), wouldn't that be a huge security risk? Someone could just modify the config files of my application to point to a potentially dangerous script, couldn't they?
On the other hand, plenty of applications allow this, while requesting admin privileges, so I guess it must be ok, but I thought I'd better seek advice before opening wide security holes everywhere =)
Can I allow my application running with full privileges to launch user-specified scripts?
You can restrict access to your config in different ways - from obfuscating the config file to using NTFS permissions to limit access of non-admin accounts to it.
C# certainly allows you to run a user script. System.Diagnostics.Process makes that real easy. The question of security here is another problem.
Running scripts when a process completes can be an incredibly useful and can make or break your target audience's opinion of your application. Understandably, you don't want your product to be turned against your own consumers through a malicious hack like you're thinking.
The root of this problem is that your options are (I'm assuming) text based and easily editable. Your best bet is to encrypt your config file to prevent outside changes to it. Note that this doesn't prevent people from using your app to change your options to allow a malicious script, but for somebody to do that, they need access to an instance of your application instead of simply file read/write access.
This does bring to question one more aspect you should watch for. Don't use the same key for every installation of your application. If you do that, then Bob could cause Alice to run a malicious script by copying Alice's config, using his instance of your app to decrypt it and make the change and then Bob can replace Alice's config with the new malicious config.
Here is another SO question for how to encrypt strings in C#.
I have been trying to understand what should be the right way in using BackupRead and BackupWrite for backing up data on a computer and especially about restoring it reliably.
Now I understand how to use the API and have been successful. However there's one thing that bothers me.
You can backup, beside the file content itself, any alternate data streams also the security information (ACLs).
Now if I would store the ACL data for backup and then later, once the data needs to be restored on a different machine OR a newly setup machine what should I do with the SIDs which are related to the ACL?
The SID is most likely no longer valid for the machine and how should the right user be selected?
Now I am looking at this on a bigger scale let's say this is a computer with multiple users and hundreds or thousands of objects with different settings this would be mess to get the data restored with the security settings applied to them again.
Is this something, if the user of the software wishes to backup the security settings, what the user has to take about himself and update them accordingly or what?
Additionally BackupRead and BackupWrite will give me the raw binary data of those items which is not all too hard to use however obviously this API does not even intend to face this issue.
Anyone has an idea how a backup application should handle this situation? What is your thought, or any pointers on guidelines for this specific topic?
Thanks a lot.
I think you understand correctly the problems with backup and restore of data. I think that correct understanding of problems is a half of its solving. I suppose that you are, like the most of users of the stackoverflow site, mostly software developer and not an administrator of a large network. So you see on the problem from another side of software developer and not from the side of the administrator. An administrator knows the restrictions of backup and restore of ACLs and already use it.
In general you should understand that the main purpose of backups to save the data and to restore the data later on the same computer or server. Another standard case is: one restore backup from one server to another server after the changing of hardware. In the case the old server will no more exist. Mostly one makes backups of servers and organize to work on the clients so, that no important data will be saved of the client computer.
In the most cases the backed up data has Domain Groups SIDs, Domain Users SIDs, well-known SIDs or SID aliases from the BUILTIN domain in the security descriptors. In the case one need make no changes of SIDs at all. If the administrator do will make some changes in ACL he can use different existing utilities like SubInACL.exe.
If you write Backup/Restore software which you want use for moving the data with the security information you can include in the backup some additional meta-information about the local SIDs of accounts/groups used in the saved security descriptors. In the Restore software you can provide the possibilities to replace SIDs from the saved security descriptors. Many year ago I wrote for one large customer some utilities to clear up the SIDs in SD in the file system, registry and services after domain migration. It was not so complex. So I suggest that you could implement the same feature in you Backup/restore software.
I do believe the Backup* APIs are primarily intended to backup and restore on the same machine, which would render the SID problem irrelevant. However, assuming a scenario where you need to restore a backup on a new install, here's my thoughts on solutions.
For well-known SIDs such as Everyone, Creator Owner and so on, there isn't really any problem.
For domain dependent SIDs you can store them as is, and upon restore you could fixup the domain part, if needed. Likely you should store the domain name as well for such SIDs.
For local users and groups, you should at least store the user/group name for each SID. Fixup on restore could be partially automatic based on these names, or manual (assuming an user interface for the application) where you ask the user whether he wishes to map this user to a new local user, convert these SIDs to a well-known SID, or keep as is.
Most of the issues related to such SIDs can (and probably typically will) be possible to handle automatically. I'd certainly appreciate a backup application that was smart enough to do the restore I asked it to and figure out that "Erik" on the old machine must be "Erik" on the new machine as well.
And a side note, if you do decide to go with such a solution, remember how annoying it is to start an overnight data transfer just to get back to something 5% done blocking on a popup it could just as easily defer :)