Can write to a read-only folder - asp.net

The environment is Windows 2008 R2, ASP.NET 4, IIS 7. I have a scenario where a user submits some settings to the server, and the server generates a file based on the settings (either a bitmap or an SVG file) and saves the file into a folder. The image is generated by writing a bitmap and the SVG file is generated by using File.WriteAllText. The user is then redirected to that file.
What I did not expect is that the server was able to create the file without me giving write permissions to the folder. Things I checked:
w3wp.exe is running under the IIS AppPool/MyUser, the correct app pool identity
IIS AppPool/MyUser has read permissions to the folder -- if I go to Security/Advanced/Effective Persmissions and check the permissions for MyUser on the folder, I get List Folder/Read Data, Read attributes, Read extended attributes and Read permissions
If I grab System.Security.Principal.WindowsIdentity.GetCurrent().Name right before the file is written, it's correctly set to the application pool identity.
The created file's owner is MyUser
What I don't understand is why ASP.NET can create a file in a folder to which the application pool has read-only access?

Turns out the Users group had Special permissions of Create File on the folder. Not sure why that is added by default in Windows 2008 -- on all my server boxes, new folders are created with Users having Special permissions of Create Files and some others. The behavior is different on Windows 7 -- no special permissions are added to the Users group.
Anyways, removing that permission addressed the issue.
Thanks.

Related

Problem with IIS for creating file on Servers Folder

I have an AspNet App (Blazor) running on IIS server.
I would like to create a txt file on the server, but it doesn't work.
I changed the AppPool identity to a domain user accound and the directories in E: have full permissions for this account.
It works in VisualStudio IIS Express, but not in IIS.
Anyone here who can help me? A permission problem`?
C# Code for creating txt file:
File.WriteAllText(#"E:\Publish\Export\Test.txt", "Hello World");
If you want to save to a specific path, use MapPath (or Server.MapPath) to get the physical path corresponding to the application. Because by default the web server (IIS or local development server) will save to its working directory.
Also you need to make sure the account running IIS has read/write permissions to the directory you need to write to. If you're looking for user accounts, go to "Advanced Settings" under Application Pools and check what's set for "Identity".

Cannot read configuration file due to insufficient permissions on web.config [duplicate]

HTTP Error 500.19 - Internal Server Error
The requested page cannot be accessed because the related configuration data for the page is invalid.
Error Code : 0x80070005
Config Error : Cannot read configuration file due to insufficient
permissions
When add new web application in IIS 7.5 and run it, this page shown to me, how to solve this problem win7 ultimate visual studio 2010
The message is clear.
Cannot read configuration file due to insufficient permissions
How to solve it.
Every asp.net application is run under one pool assigned to it, and each pool is run under a specific account.
Open the IIS, locate the pool under which your app is try to run, see the user that is assigned to that pool, and give read permissions to that user on your full site directory tree.
Especial for the web.config
The web.config, its the configuration file that message says, must have (and) write permissions.
So you locate web.config on the root of your site, right click on it, go to permissions and give on the pool-user, the write capability. The pool user, is the user under the witch the pool is run, as I explain below.
More details
To been able to run a public asp.net site with IIS, each file on the directory must have permissions for two accounts.
One account that is permitted for public access, and the account that assigned to that application pool have.
To find/assing the first account you go to your iis site | Authentication | Edit, and see or change it as you see on that screen shot.
Now note that name and we going to find the user under with the pool run.
Go the your IIS Site and click on the Basic Settings to find the pool name, then go to the IIS | Application Pools and see the Identity column, and note the name of the user under the witch your site is run.
Now that we have the two users names we go to the root of the site and set the minimum of permissions that is the read as
Some Notes
If the IIS_Public_ACCESS_USER is not give read permission the site is run, but ask for password
On some directories you need and write permissions, if you let for example your users upload images, or keep on App_Data, some database files. Only for that directories you give and the write permissions to the IIS_POOL_USER.
Some directories, like the App_Data and App_Code have direct protection from asp.net and they not allow anyone from the client side to run or view whats is in there.
On the public directory that allow write access to your user add one web.config and totally disable all the running of asp.net files.
More to read for the directories that give write permissions I've been hacked. Evil aspx file uploaded called AspxSpy. They're still trying. Help me trap them‼
It looks like your IIS_User doesn't have the necesarry permissions to access your website in C:\Users....\Visual Studio 2012\Websites...
Also make sure your application is running the correct .NET version (2.0, 4.0, ...)

How to set correct file permissions for ASP.NET on IIS

HTTP Error 500.19 - Internal Server Error
The requested page cannot be accessed because the related configuration data for the page is invalid.
Error Code : 0x80070005
Config Error : Cannot read configuration file due to insufficient
permissions
When add new web application in IIS 7.5 and run it, this page shown to me, how to solve this problem win7 ultimate visual studio 2010
The message is clear.
Cannot read configuration file due to insufficient permissions
How to solve it.
Every asp.net application is run under one pool assigned to it, and each pool is run under a specific account.
Open the IIS, locate the pool under which your app is try to run, see the user that is assigned to that pool, and give read permissions to that user on your full site directory tree.
Especial for the web.config
The web.config, its the configuration file that message says, must have (and) write permissions.
So you locate web.config on the root of your site, right click on it, go to permissions and give on the pool-user, the write capability. The pool user, is the user under the witch the pool is run, as I explain below.
More details
To been able to run a public asp.net site with IIS, each file on the directory must have permissions for two accounts.
One account that is permitted for public access, and the account that assigned to that application pool have.
To find/assing the first account you go to your iis site | Authentication | Edit, and see or change it as you see on that screen shot.
Now note that name and we going to find the user under with the pool run.
Go the your IIS Site and click on the Basic Settings to find the pool name, then go to the IIS | Application Pools and see the Identity column, and note the name of the user under the witch your site is run.
Now that we have the two users names we go to the root of the site and set the minimum of permissions that is the read as
Some Notes
If the IIS_Public_ACCESS_USER is not give read permission the site is run, but ask for password
On some directories you need and write permissions, if you let for example your users upload images, or keep on App_Data, some database files. Only for that directories you give and the write permissions to the IIS_POOL_USER.
Some directories, like the App_Data and App_Code have direct protection from asp.net and they not allow anyone from the client side to run or view whats is in there.
On the public directory that allow write access to your user add one web.config and totally disable all the running of asp.net files.
More to read for the directories that give write permissions I've been hacked. Evil aspx file uploaded called AspxSpy. They're still trying. Help me trap them‼
It looks like your IIS_User doesn't have the necesarry permissions to access your website in C:\Users....\Visual Studio 2012\Websites...
Also make sure your application is running the correct .NET version (2.0, 4.0, ...)

ASP.NET/IIS7.5 Writing Log File Not Working (Permissions, UAC, Config., ???)

We're having trouble migrating our ASP.NET applications to Windows Server 2008 R2 x64 and IIS7.5. The problem is that our ASP.NET apps write log files, and these log files are not being written. The only way the apps write their log files is if I'm logged into the server as the local Administrator user or if I right click and run IE as Run as Administrator, neither of which is an acceptable solution for us.
Our platform is:
Windows Server 2008 R2 x64 (UAC setting is the default setting)
IIS7.5
ASP.NET 4.0 (using Windows authentication and impersonation, both on in web.config)
Our app gets installed to:
D:[appname]
[appnameWebSite] (all the .aspx, .dll, etc. files are in here)
\Log (the app tries to write the log file to this folder)
On the server:
Created new App Pool (name: [appname], .NET 4.0, Managed Pipeline Mode: Classic, Identity: ApplicationPoolIdentity, Load User Profile: False, all other properties are the defaults)
Created IIS application pointing to D:[appname][appnameWebSite] and added it the the new App Pool (Full trust level)
Have a domain user in local Administrators group
With all the configuration and default settings listed above, the ASP.NET app will not write the log file. The app appears to work fine in the browser, but no log.txt file.
To try to "fix" this issues, we've tried many things:
Tried Application Pool setting: Managed Pipeline Mode: Integrated
Tried Application Pool setting: Identity: NetworkService
Tried Application Pool setting: Identity: LocalSystem
Tried Application Pool setting: Load User Profile: True
Gave Users group full control to file system for our application folder structure (tried appname folder, tried Log folder only, tried appnameWebSite and Log folders only)
Gave IIS AppPool[appname] (matching the new App Pool) user full control to file system for our application folder structure (tried appname folder, tried Log folder only, tried appnameWebSite and Log folders only)
None of these things helped. Again, the app would run fine, just no log file created.
As mentioned above, the only way that the log file is created when the app runs is if we log into the server using the local Administrator account (which makes sense since he's a super user) or if we run IE as administrator and elevate privileges.
Any suggestions? Help? Questions?
Thanks!
I tried granting every permission possible and still wasn't getting any log files. Finally I came across this which suggested changing the ownership of my logfiles directory. I checked, and the directory ownership was set to SYSTEM. I changed it to Administrators and applied the change recursively. I bounced IIS, hit a webpage from the site in the browser, and now I have log files. Hooray!
Note: the thing that tipped me off was checking the System event log. I was getting 15006 errors saying "Owner of the log file or directory C:\inetpub\logfiles\W3SVC1\some.log is invalid. This could be because another user has already created the log file or the directory."
Well, after days of trying every IIS option, user and group accounts, file system permissions, Process Explorer, etc., I think we got it working:
We reset all our IIS app pool and web site settings to their default values
We also reset the folder/file system permissions on our Log folder to the default settings
Then we turned off Internet Explorer Enhanced Security Configuration on the server
And success! The log file is written as expected no matter what user is using the ASP.NET application, and no matter if they're running it on the server itself or from a workstation.
I don't know if turning off Internet Explorer Enhanced Security Configuration on the server is the "correct" thing to do or if it violates any best practices, but it seems to work for us.
Does anyone have anything to add?
I struggled with this one for a while. The ApplicationPoolIdentity is a member of the Users group and the Users group has limited access.
From Explorer, right-click on the folder where you are trying to write and go to Security. Click the Advanced button. you will see that Users have Read and Execute permission and the Users group may or may not have Special permissions. If not, Click on Change Permissions and give Users the ability to Create files / write data and Create folders / append data. This is restricted to this folder. I usially use a subfolder so that I not provide write access to my whole website.
Try creating log files again. This is the only permission that I needed to set to make it work.
For me the trick was giving write access for SYSTEM and Administrators not only to the log folder itself, but also every folder in the path. This is not how permissions usually work in Windows, but IIS appears to be really rather particular about it. Not that there is a good reason to remove these two from the ACLs to begin with.
If you suspect this to be the problem, check the Event Log under Windows Logs / System. This issue manifests itself as an Error entry from source HttpEvent, and reads "Unable to create log file C:\path\to\logs\W3SVC1\u_extend1.log. Make sure that the logging directory is correct and this computer has write access to that directory."
P.S. This is true for IIS 10 but may apply to other versions too.

No access to files in iis7 mvc app - server 2008 r2

I've just installed windows server 2008 r2 along with visual studio and dropbox. I'm using it as a VM for development and dropbox helps me keep my files in sync with other machines.
I've got my site set up in IIS but I'm getting an access denied error when trying to view the site. I've had this before and to get around it in the past I've gone through and added the IIS_User account to the list of permissions to read/modify the files. I assume because the file's have been copied down with drop box the files don't have the necessary permissions. Here's the bugger, I can't batch update the files by modifying permissions on a folder, I'm having to do it right to the file level and even worse, one at a time! I can't have this.
I'm relatively new to 2008 r2 and IIS 7 so I have no idea what's happening here. Can someone explain what is going on and if there's an IIS/file permission setting I can update to resolve it at the top level folder?
I've tried adding anonymous permssions on the website in IIS and I've added permissions on the folder for IIS_User (even Everyone). I have an Administrator account and that's already set to allow me to read/write/modify the files.
This is typically the message I'm getting 'An error occurred loading a configuration file: Access to the path X is denied'.
This is happening on ascx & aspx files as well as config files.
Edits:
The site is visible when debugging from Visual Studio.
The site is operating in Full Trust (internal)
Please help, this is stopping me from working and driving me insane!
By default in IIS 7, websites run as the local system's network account (NetworkService), not as IIS_User.
To verify, in IIS Manager, select the Site in question, click Basic Settings... and check the Application Pool it is assigned to. Then go into Application Pools and check the Identity for that Application Pool. Make sure that user listed is in the ACL.
Adding Everyone to the ACL should work instead, but just in case I would suggest you check the above. Also of course make sure when you set the ACL to check the box for resetting inheritance on all subfolders, if that is appropriate for your application.
You could also try setting the identity of the application pool to a local (or domain) user you have created which has access to your application directory.
Hope that helps.
Regarding whether other identities would work for your app pool, that depends entirely on whether those identities have permissions to all the files and/or databases and other resources you application needs to access. Right now you have the application running under your user account, which is generally not recommended. IIS has your password cached, and if you change it, your application will stop working until you update the application pool configuration.
As far as setting NTFS permissions, it can get tricky. Once you have disabled permissions inheritance, that file or folder will need to be updated individually every time you need a permission change. The flip side of this is that you cannot remove inherited entries on an ACL, you can only add to them. However you can design a strategy that offers a baseline level of permission at the root of a file structure, and then add permissions to subfolders/files.
In order to check & reset inheritance on a folder, go into its properties, security tab, click advanced, then click Edit. You can see whether this folder inherits permissions from its parent, and optionally wipe out all subfolder/file permissions and enable inheritance on all child folders & files.
Hope this helps.

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