I have two ASP.NET web applications and in both I use EventLog.WriteEntry with a custom source name to write custom events to the application log.
Both on my programming machine and on the webserver this works in one of the applications, in the other it doesn't - I get a security exception:
[SecurityException: The source was not found, but some or all event logs could not be searched. Inaccessible logs: Security.]
I am wondering why this happens, both web applications are identical (as far as I see it). The only difference from a security point of view is the authentication mode: one uses Forms (there Eventlog.WriteEntry works) and one uses Windows (here it doesn't work). Can this be the reason?
Giving "everyone" read access to the application log doesn't change this behavior.
Your problem on Windows authentication mode essentially similar with these problems:
System.Security.SecurityException when writing to Event Log
System.Security.SecurityException: The source was not found, but some or all event logs could not be searched. Inaccessible logs: Security.
The exception means that your web app tried to write on event log using a value given to "source" which has not been registered due to insufficent privilege on corresponding account.
When using Windows authentication mode to perform event log tasks, you need to give read permission on NETWORK SERVICE account on eventlog\Security key. Below are these steps to do:
Open Regedit (Registry Editor).
Go to HKLM\SYSTEM\CurrentControlSet\services\eventlog\Security
Right click the branch, select "Permissions".
Click "Add", find RDN named NETWORK SERVICE or type it directly, then add the account.
Under "Permissions for Network Service", check "Read" or "Full Control" to give the read permission, then apply the change.
Restart your application pool on IIS host.
If it still not enough, do actions below:
Open IIS Manager. Check the Identity column on Application Pools section, it should given LocalSystem or NetworkService.
When you need to change Identity, right click the application pool with Windows authentication, choose Advanced Settings.
Under Process Model, change ApplicationPoolIdentity to LocalSystem or NetworkService, apply your edit and restart the application pool.
NB: NetworkService identity is more preferred to LocalSystem due to security vulnerability reasons.
Also you may try setting <trust level="Full" /> in web.config file, depending on security consideration.
If all solutions above still won't work, set Visual Studio on development machine or deployed app on web server to run as administrator privilege, gaining full access to Windows authentication event log. After all, it depends of your choice to ensure proper security measure was applied.
Related
CONTEXT
My client has an ASP.NET web application running in IIS 10 on Windows Server 2016. The web application needs to access files on network shares on different servers in a WORKGROUP environment. So, I created the same local user account on all servers, set the password to all the local user accounts to be the same, granted said user with full control permissions to the network shares, and reconfigured the IIS application pool to run under the identity of the aforementioned local user account. There is also a custom Windows service running under the same local user account for the same reason: to access files on remote network shares. All of this works fine. The web application and the Windows service can successfully access files from the network shares residing on servers other than the server on which IIS and the custom Windows service are both running.
ISSUE
However, there is a feature in the web application when an authorized user modifies a particular validation matrix record, it triggers a custom command sent to the aforementioned Windows service to cause the service to update its in-memory copy of the validation matrix. This worked fine when the IIS application pool was running under the built-in ApplicationPoolIdentity which apparently has permissions to interact with Windows services. But, the feature fails when the IIS application pool is running under the identity of the aforementioned local user account. The message in the exception is: Cannot open {SERVICE_NAME} service on computer '.'. Again, the Windows service and IIS are running on the same server. And recall that the Windows service is running under the same local user account as the IIS application pool identity.
QUESTION
How do I grant permissions to the local user account to allow said account the ability to issue the custom command to the Windows service from within the ASP.NET web application?
RESOLUTION ATTEMPTS
I've tried using subinacl.exe in an attempt to grant the necessary access but never got it to do anything other than to indicate Done 0, Modified 0, Failed 0, Syntax errors 0. I'm using version 4.2.1.1604 and executing it from an Administrative Command Prompt. The syntax I used was:
subinacl /service customServiceName /grant=localUserAccount
and the result is below
+service customServiceName
/grant=localUserAccount
Elapsed Time: 00 00:00:00
Done: 0, Modified 0, Failed 0, Syntax errors 0
I also tried /grant=localUserAccount=U and /grant=localUserAccount=F but to no avail ... same results as shown above.
I admittedly am not familiar with subinacl.exe and I saw somewhere that someone indicated earlier versions of subinacl.exe are buggy and suggested using version 5.2.3790.1180 which I cannot find. Result: failed.
I have added the local user account to the Administrators group on the server where IIS and the Windows service are running. Result: failed. CORRECTION 02/13/2023: This succeeded but required a server reboot for it to take effect. To be clear, I do NOT want to permanently add this user to the Administrators group. This was simply a test. As far as the server reboot being required for this to take effect is concerned, I tried recycling the application pool in IIS, restarting the Windows service of interest, and restarting the World Wide Web Publishing Service but no joy. Only a server reboot caused the addition of the local user account to the Administrators group to take effect from the standpoint of said local user having permissions to send a custom command to the Windows service from within the web application. I absolutely am inclined to believe that there is a better way to achieve the desired end without adding the local user account to the Administrators group. Surely someone else before me has encountered this and solved it.
The local user account is already set up in the Local Security Policy with the ability to "Log on as a service".
I have reconfigured the IIS application pool identity to NETWORK SERVICE and granted NETWORK SERVICE full control permissions to the network shares (which are on a different server in a WORKGROUP environment, not a domain environment). In this configuration, the feature to update the Windows service works, but access to the network shares is denied ... likely because NETWORK SERVICE is a built-in local account [with no password?? not sure on this] and does not behave the same as a "regular" local user account.
So, I have a catch-22 that has me stumped. I would be grateful for any insight on this dilemma.
Cheers!
I want convert to application my Asp.Net app.
I created application Pool what use service account. And want "convert to application" under this application pool.
BUT if i check connection setting show me error "Invalid application path".
When I set my personal user account in to "connect as"
everything was alright.
Question : what must fulfill service account to right use? Or any suggestion whot I must change, try or verify?
You should be able to use the Setting "ApplicationPoolIdentity" for Identity in the Pool Advanced-Properties.
Usually your folder security settings must grant read, execute, browse folder and read for the local group IIS_IUSRS.
if you did both, the conversion to application should work.
Short version:
For IIS 7.5 web applications with Windows Authentication does the end
user need to have Read file access?
Long version:
I have an intranet ASP.NET web app that uses windows authentication. It's installed at dozens of different companies and normally the authentication works fine: users navigate to the site e.g. http://appserver/MyApp, the app recognizes who they're logged in as and displays pages accordingly. I just installed it at a new client and encountered a problem:
When connecting e.g. to http://appserver/MyApp I'm prompted for windows credentials but after entering them I'm repeatedly prompted. After several re-entering credentials I'm shown a 401 error page saying "401 - Unauthorized: Access is denied due to invalid credentials.". So not only is it not passing through my identity but even when entering the username & password it's still denying access.
Giving Read & Execute permissions to the end users of the app solves this problem, but I don't think this should be necessary at all.
In the windows Application Event Log there's a message "File authorization failed for the request" along with Thread account name: NT AUTHORITY\NETWORK SERVICE and User: [the correct workstation users's domain account]. This suggests that the file access is being performed with the User's identity, not the AppPool identity of Network Service. Sure enough if I grant the end user Read & Execute permission (I didn't try Read only) to the application's directory then everything works correctly: when the user browses to the site they're authenticated automatically, not prompted, and the web site correctly recognizes their identity! Therefore my workaround solution is to give Read & Execute permission to Everybody on the application directory...but this is not an ideal solution.
This seems very strange. I've never needed to do this before in IIS 7.5, so far as I recall, and definitely never needed to in IIS 6 or IIS 7. Is this a new IIS7.5 thing? The documentation says that Impersonation is turned off by default. I added a element to the web.config to be sure, removed file permissions other than Network Service, but the problem remained.
Any thoughts? Is it normal for Windows Authenticated sites on IIS 7.5 for end users to need file permissions on the web server files?
Some relevant details:
Network Service
has Full Control file permissions to the app folder.
When connecting from the server itself I was prompted for credentials
but after entering them i'm authenticated and the application works
correctly including displaying my windows login and connecting and
retrieving data from the db. I later determined that it was prompting
for credentials because http://localhost was in the trusted sites
and therefore not recognised as the Intranet Zone and thus not
passing identity through. I also determined that it was working as
this user identity because it's an admin user who has file
permissions.
The web server is running Windows Server 2008 R2 / IIS
7.5. It didn't have IIS on it until I installed it. I installed the default features as well as Windows Authentication, ASP.NET, and
possibly a couple of other items. A separate WCF app I installed that
uses IIS, anonymous authentication & .net 2.0 is working fine on
that web server.
The app install process is a manual copy of files,
creation of IIS App Pools & web apps, updating connection strings,
etc.
I checked the IE security settings. It was recognizing the
server as in the Intranet zone and had the option 'Automatic logon
only in Intranet zone' selected. Also on Advanced Settings the
'Enable Integrated Windows Authentication' option was checked.
After
installing IIS I ran aspnet_regiis -i for .net 2.0 and
aspnet_regiis -iru for .net 4.0.
Anonymous authentication is
disabled for my app and Windows Authentication enabled.
The app is
running on ASP.NET v4 but there's another app I installed
experiencing the same issue running ASP.NET v2.
The app is running
with Identity = Network Service and in 32-bit mode.
Database
connection string includes Trusted Connection=True and database
permissions are granted to the web server account [domain]\[server]$
e.g. DGM\MyServer$.
In IIS > Authentication > Windows Authentication > Providers the list was Negotiate first then NTLM. I tried reordering so NTLM is first.
In the Windows Security Event Log there
were a series of Microsoft Windows security auditing events: Logon
and Logoff. They indicated that the Logon was successful and was
displaying the User Id of the workstation user. This are from when
I'm connecting from another workstation and receive a 401
Unauthorized after several attempts.
I see someone has had this problem reported here but with no solution. Originally I posted in the ASP and then the IIS forums with no answers so far.
Update:
This msdn article says
When Windows authentication is enabled but impersonation is disabled, ASP.NET performs file access checks in the file authorization module using the credentials that are sent from the browser (my emphasis). Impersonation does not need to be enabled, because the FileAuthorizationModule module ensures that the requesting user is allowed read access or write access to the resource, depending on the request verb (for example, GET or POST) before executing the request. This behavior applies to any requests that enter managed code. In earlier versions of ASP.NET, accessing files based on URIs such as "Default.aspx" triggered the access check. In ASP.NET MVC applications, where access to resources is typically performed using extensionless URLs, this check typically does not apply, because there is not a physical file to check. In that case, the FileAuthorizationModule class falls back to checking access-control lists (ACLs) for the folder.
This does suggest that the end user needs permissions to the files (in the case of .aspx) or the folder (for MVC) ... although still this seems slightly tucked away and non-definitive. This article about App Pools says they're used as the identity for securing resources, which contradicts the idea of needing to grant privileges to end users. Unless the rules are different for App Pools and NETWORK SERVICE, which could be the case but would be surprising.
Are authenticated users allowed to the app folder?
We were also fighting with this issue, and started setting up security groups so we could give our users file level permissions. Then one of our server admins stumbled across a couple of new properties that allow the app to authenticate to the file system under set credentials, and resolved the need for the users to have access. Here is what he came up with…
There are two IIS settings that control this:
Physical Path Credentials Physical Path Credentials Logon type
By default, Physical Path Credentials is set to Application User
(Pass-through authentication). This means that IIS doesn’t do any
impersonation when handling Windows Authentication requests. This can,
however, be set to a specific user (though not, unfortunately, the
application pool identity, which would be ideal). Physical Path
Credentials Logon Type is set by default to Clear-Text. For my testing
I set this to Interactive (though this may not be the correct value).
Possible values are Clear-Text, Batch, Interactive, and Network.
To set this up I did the following:
Created a local account (IIS-AccessUser)
Granted IIS-AccessUser read and execute access to the /home directory of the site.
Added IIS-AccessUser to IIS_IUSRS group (necessary for accessing .NET temporary files)
Set IIS-AccessUser as the Physical Path Credentials
Set Physical Path Credentials Logon Type to Interactive
Doing the above allowed me to log in to the application directly,
without having to allow Authenticated Users, or me having to be a
member of any of the groups in the /home folder. It also still
preserved .NET Authorization roles, so I still could not access parts
of the site that I was not allowed to.
The short answer is NO. You are not required to grant file access permissions when using Windows Authentication in IIS 7.0 and IIS 7.5.
We were only able to discover this because our server admin smelled the security and management issues that arise from taking the route of granting file level access to users and groups.
For anyone dealing with this issue or if you are setting up a new IIS7/IIS7.5 server and/or moving from IIS 6, here is an article that gives you all of the Windows Authentication options and configurations that need to be modified to avoid granting file level access to individuals or groups.
Please read the two comments in at the end of the POST for some valid critiques of the methods used in this article.
http://weblogs.asp.net/owscott/iis-using-windows-authentication-with-minimal-permissions-granted-to-disk
In addition to the information in the article, please be aware that IIS 7.5 is not using the web configuration tags for system.web (at least not in my MVC 4 application).
It is looking in the system.webserver tags for authorization configuration (where you will need to list the windows domain\groups a user needs to be in to access your application).
-- DSB
I have a website in IIS 6.0 using an application pool with a custom service account. When I browse the website, I get an error "service unavailable" and the error in event log says
The identity of application pool 'SampleAppPool' is invalid, so the World Wide Web Publishing Service can not create a worker process to serve the application pool. Therefore, the application pool has been disabled.
I think the utility "Aspnet_regiis" can be used to grant access to an account to IIS metabase according to this article, but is that the right way to fix this issue? Because this utility is used for multiple things and may do more than just granting the permissions to the account, or should I just add the account manually to IIS_WPG group?
When I see this in IIS 6 and the user has a custom app pool identity, the problem typically originates in the entry of credentials in the app pool properties. So there are generally two origins for the issue.
One is a simple typo in the credentials, unfortunately the form validation is not very good in IIS 6, so I often will have users change the identity of the app pool, then immediately check that the credentials "took" and/or check the System event log for W3SVC and related errors.
The second specific cause I see in this scenario is when people enter an Active Directory user, they sometimes forget to add the domain name. (e.g. DOMAIN\Username). Which leads me to the next point, the IIS_WPG is the builtin local group which grants members the required ACLs to run as an app pool identity. The aspnet_regiis.exe -ga grants the same thing to users, but IMO it is best suited for use when the IIS_WPG group is not an option. Also a dedicated app pool user account is generally a good idea. If the AD user password is changed, you'll bring your app to its knees until you again re-enter the credentials in the IIS Manager.
Edit: I added some para breaks to make this chunk more readable.
I had this same problem and I resolved it by starting the application pool. Ours was stopped even though IIS was running.
"The identity of application pool 'SampleAppPool' is invalid..."
Every time I have had that error, it was because the user name and password where not correctly entered in the application pool. This happens also when you import the pool settings from another server. Reentering the password in the application pool identity configuration has always solved the problem.
Once you get that right, you will probably meet the second problem you are describing, but that's an unrelated issue. It can be fixed as you describe, or even manually granting the required access permissions to the application pool identity.
If you are connecting to a remote machine using one or more remote access tools, take note: your keyboard mappings may be getting screwed up somewhere along the way!
In my case, I tried typing out certain letters of the password in a plain text editor on the remote machine (not necessarily in the same order, to retain security). When attempting to type the dollar character, I found that if I used the left shift key I got a "$" but if I used the right shift key I got a "4".
Once I had that figured out, I could enter the correct password for the Application Pool Identity. (Note: when filling out the identity section, IIS does not validate the password you enter against the user identity, only that the two passwords you enter match each other).
My ASP.NET MVC 2 application runs under built-in local NETWORK SERVICE account. I want to set up access permissions for the folder which resides in another computer, but in the same domain. I located that folder right-clicked to open its properties form, clicked to Security tab and pressed Add button which displayed Add user form with correct domain name in the location field. I referred to the account with following syntax:
<domain name>\<server name>$
because I learned that NETWORK SERVICE account uses machine account when connected to other computers in the domain.
However, the system couldn't find the account, so refuses to add the account. Without the domain name it adds a user, but that user seems to be local user, not web server's NETWORK SERVICE account. What am I doing wrong?
By the way, the above syntax worked when I created login for the sql server which is different computer from the web server.
OK, I will answer my own question. The above syntax \$ was correct. Just make sure to select computers checkbox in the object type, when adding user permissions.
I have been in this same situation before. I don't think I got it to work with the Server/Network Service but this might be worth a try.
Figure out the account network service is using to access the network resource.
Configure windows auditing (on the server the folder is located) to log the failed security events of the folder.
or monitor the folder with something like filemon.exe
.. from here you can try and add the account to the security settings of the forlder. (IIRC I did'nt ever get this to work)
Alternatively you can ensure the action is performed under the context of a domain user. Either by:
Impersonating the user in code and performing the action (my preference)
Setting the impersonation settings in web.config to a named user
setting the application pool to run as a domain user.