403 Forbidden Error - IIS 8 - iis

I'm using IIS 8 on Windows 2012 server. I have a site set up to serve as an API for HTTPS traffic on a custom port (4443). I have installed a wildcard SSL certificate, which is functioning properly. Our network firewall is routing all public inbound traffic on port 4443 to this server internally, which is then being handled by IIS.
From the server itself, everything works fine. I am not using localhost, and do not have a hosts file entry looping the traffic back internally. Going to https://api.blahblahblah.com:4443 returns what I want.
However, from external to the network, I am getting a 403 Forbidden error. I know the traffic is making it to the server because I get the correct custom "X-Powered-By" response header that I have set on that server.
I have tried setting the permissions on the folder that contains the site files to allow Full Control to "Everyone", but no luck. The site has Anonymous Authentication enabled for the user "IUSR". Directory browsing is disabled.
What's going on? I'm assuming it's a permissions error with the file system, but I figured having the Everyone permission would eliminate that. Also, there is nothing special about the internal traffic (from the server itself) in terms of an authenticated session or anything. It's just a plain request with no bells or whistles.
Please help! Thanks.
=======UPDATE=======
Here is a sample log entry showing the substatus code of 16:
2018-02-08 17:56:58 10.1.10.11 GET /favicon.ico - 4443 - 184.4.143.229 Mozilla/5.0+(Windows+NT+10.0;+Win64;+x64)+AppleWebKit/537.36+(KHTML,+like+Gecko)+Chrome/63.0.3239.132+Safari/537.36 https://api.blahblahblah.com:4443/data/countyList 403 16 2148204809 97
Apparently this is a client certificate trust issue? Upon further testing, I am able to access the site without issue on another device, just not my primary development PC.
I just set the site to Ignore Client Certificates in the SSL Settings, and it is working as expected again.

A 403 error could occur due to multiple reasons. Could you please share the substatus code. You can find it in IIS logs. Default location - C:\inetpub\logs\logfiles\w3svc_websiteID.
Once you have the substatus code, please share it here.
You can also capture FREB logs by following this article - https://learn.microsoft.com/en-us/iis/troubleshoot/using-failed-request-tracing/troubleshooting-failed-requests-using-tracing-in-iis
Just modify step #10 in this article and don't uncheck anything in your case (leave everything to default). This will clearly tell you what's going on in the IIS pipeline.
If its 403.14, just add a default document in IIS and you should be good to go.

Related

Localhost webserver denying PUT request

I have configured a webserver on localhost with https using Microsoft IIS Administration. I am able to browse directory with files with browsers and Visual Studio using localhost prefixed with https, such as https://localhost/trial etc.
I wish to upload a file to the said directory, ie., trial, using Libcurl to test some features. Unfortunately I'm unable to do so.
Using the same Libcurl example as given on
Libcurl File Upload
-modified for https, the console window tells me that the following has occurred, upon running the code :
IIS 10.0 Detailed Error - 405.0 - Method Not Allowed
HTTP Error 405.0 - Method Not Allowed The page you are
looking for cannot be displayed because an invalid method (HTTP verb)
is being used.
I checked the IIS Administrator and saw that all authorizations are allowed. I suppose the fact that it is flagging a HTTP verb issue rather than HTTPS as I'd enabled and used as URL in code isn't a big thing?
Libcurl uses PUT for uploading files, so should be an allowed verb.
I am quite new to this, so I'm not certain I did something incorrect with the setting up of the webserver, or whether there are security issues or permission issues which are causing a problem here.
As far as I know, there is impossible to use http put or post a file to a IIS web application's folder without writing server-side code. Otherwise, configure an FTP site on your IIS installation. Then you could use ftp command to upload the file.
If you really need using HTTP put or post to upload the file, you could consider using WebDav.
More details about what is webdev and how to use it, you could refer to below article.
https://learn.microsoft.com/en-us/iis/install/installing-publishing-technologies/installing-and-configuring-webdav-on-iis
https://learn.microsoft.com/en-us/iis/get-started/whats-new-in-iis-7/what39s-new-for-webdav-and-iis-7
Try hostname instead of localhost
Add a trailing slash (/) for the directory.

Application Request Routing: Why some sites return HTTP 404 some don't?

I want to add a load balancer to an existing asp.net project using Application Request Routing. So I made myself familiar with the concepts and created a local test-setup:
IIS locally running on Windows 10:
Installed Application Request Routing 3.0 with Windows Platform Installer
Created server farm with following servers:
<test-server-name>.de (Microsoft 2012 R2 Server: contains the asp.net project)
www.google.com (just to see if load balancing and url rewriting works because I don't have two test servers available)
URL-Rewriting rule:
After typing localhost multiple times in any browser, I can see that load balancing (weighted round robin) is working fine. It's alternating between 1. and 2. website.
The problem I'm facing is a 404 Error on both websites.
I already tried the following:
Installing and enabling Failed Request Tracing Rules (on local IIS): URL Rewriting is working properly i think.
Failed Request Log for www.google.com: google drive, unzip and open xml in e.g. IE for better view
Create Server Farm without automatic creation of URL Rewrite rules
(selecting No and create own URL Rewrite rule)
Change "Managed Pipeline Mode"-setting of Applcation Pool from Integrated to Classic
Healthcheck on other Websites I have absolutly no clue why it's working on Git-websites and why facebook is returning a 400 error code.
Enabling/disabling proxy (IIS-Manager -> Application Request Routing Cache -> Server Proxy Settings...)
I don't know what i could do next, so I appreciate any help. Thanks.
Answer can be found here: https://forums.iis.net/t/1238739.aspx?Why+some+sites+return+HTTP+404+some+don+t+
Some websites simply don't support localhost as hostname, which is why localhost can't be found (error 404) e.g. on google.com
Detailed answer if link above is not working in future:
That is not an effective test.
What you are doing is sending the hostname of your request to the third party servers. Like Google.
So if your request is say http://example.com you are sending this to say www.google.com and the Google servers will likely reject this as you can see
Web server admins generally don't let themselves receive traffic from domain thet do not host.
If you sent a request to my servers IP with mysite.com I too would likely reject it. (Things get complex if you have wildcard sites and you allow all traffic through)
But simply showing that 404 page from Google means tour request hit there server so that implies ARR is working.
If you really wanted to test it this way have a local host file with www.google.com resolving to your servers IP. Set up a site with www.google.com as the hostheader and then you should see the correct info hitting Google. But there is no accounting for what 3rd party admins do on their side.

GET request to IIS returns Microsoft-HttpApi/2.0

I've got 6 identical machines running IIS and Apache. Today one of them decided to just stop serving requests. I can access all of the webapps when I try from localhost/resource but when I try from url/resource I get a 404. I did a Get request against the machine that isn't working and I get this back:
Server: Microsoft-HTTPAPI/2.0
Connection: close
Compared to a working server:
Server: Microsoft-IIS/8.5
X-Powered-By: ASP.NET
Content-Type: text/html
Tried searching for this problem but came up with nothing, anyone got any idea's?
Windows has an HTTP service that manages calls to IIS and other HTTP enabled services on a windows machine. Either you need to configure it to handle your calls, or, in the case of WAMP or similar non-IIS-web-server-on-windows scenarios you may just need to turn it off.
When you see "Microsoft-HttpApi/2.0" returning error, such as 400 "bad URL" or "bad header", etc. the problem is most likely because the HTTP.sys service is intercepting your http request and terminating it because it does not meet with the minimum validation rules that are configured.
This configuration is found in the registry at HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\HTTP\Parameters. In my case, it was choking because I had a RESTful call that had a 400 character segment in the url which was 160 characters more than the default value of 260, so I
added the registry parameter UrlSegmentMaxLength with a DWORD value of 512,
stopped the service using net stop http
started the service using net start http
I've run into these issues before and it is easy to troubleshoot but there is very little on the web that addresses it.
Try these links
"the underlying problem is that the client has sent a request to IIS that breaks one or more rules that HTTP.sys is enforcing"
enabling logging on HTTP.sys is described here
a list of the HTTP.sys parameters that you can control in the registry is found here.
A bit late, so put here for posterity ;-)
After trying all sorts of solutions found on the web, I almost gave up, but found this little nugget.
If the response's Server header returns Microsoft-HttpApi/2.0, it means that the HTTP.sys is being called, not IIS.
As a result, a lot of the workarounds will not work (URLScan, etc).
This worked however:
Open regedit
Navigate HKLM\SYSTEM\CurrentControlSet\Services\HTTP\Parameters\
If DisableServerHeader doesn't exist, create it (DWORD 32bit) and give it a value of 2. If it does exist, and the value isn't 2, set it to 2.
Finally, restart the service by calling net stop http then net start http
src: WS/WCF: Remove Server Header
Set below registry flag to: 2
HKLM\SYSTEM\CurrentControlSet\Services\HTTP\Parameters\DisableServerHeader
Setting this to 2 will ensure that self host WCF services no longer sends the SERVER header and thus ensure we are security compliant.
Please note that this disables ALL server headers.
The default value of 0 enables the header, and the value of 1 disables server header from DRIVER (http.sys), but app can still have headers.
For me I had to restart the server for the changes to take effect.
Hope this helps someone
I was working on our web app on a client's site and ran into an issue where the site root pages loaded, but the reports folder always returned a 404 for files that existed in the folder. The 404 page showed the .Net version of 2 when the application was set to 4, and a test of a non-existent page in the root returned a 404 page showing .Net 4.
I tried just http://localhost/reports and got back a Microsoft Reporting Services page. Not part of my application.
Be sure to check just the default document of the folder when a unexpected 404 comes up and the file exists.
This question and series of replies helped me get to the bottom of the related issue I was having. My issue centered around using just a subdomain to go to our server (e.g. typing "www/somepath" into the browser while on our corporate network), which had worked in the past on an older server, but no longer worked when the system was upgraded to a new server. I saw the unexpected Microsoft-HttpApi/2.0 string in the header when using the Chrome Devtools to inspect the Network traffic.
My HTTP.sys process was already logging, so I could verify that my traffic was going to that service and returning 404 NotFound status codes.
My resolution was to add a binding to the IIS site for the subdomain, making IIS respond instead of the HTTP.sys process, as described in this server fault article - https://serverfault.com/questions/479274/why-is-microsoft-httpapi-returning-404-to-my-network-switch
In my case, running Windows 10 Pro, it was the Windows MultiPoint Service.
By executing:
net stop wms
Port 80 was released.

IIS 7.5, URL Rewrite 2.0, Kerberos - rewritten URL returning 401.1

I would appreciate any hints regarding the following issue:
The problem summary:
While using Negotiate:Kerberos in IIS 7.5, the authorization works correctly right until we setup URL rewriting (using the MS module "URL Rewrite 2.0") - any rewritten URL then returns "401.1 Unathorized" (requests not matching any rewrite rule keep working though).
The setup:
Windows Server 2008 R2 x64
IIS 7.5
URL Rewrite 2.0
Server is in a domain
SPN exists for HOST/hostname and HOST/hostname.domain (created by default)
Pool is using default ApplicationPoolIdentity (no custom account, not network service)
Kernel mode set to OFF
Authentication providers set to "Negotiate:Kerberos" only (no NTLM or annonymous)
URL Rewrite rule as as "^(.*)/$" => "index?x={R1}"
The result:
1) When accessing any URL not matching any URL rewrite pattern, Kerberos is working correctly, i.e. Kerberos ticket is issued (verified using klist), sent (verified using netmon and HTTP headers) and accepted (verified by URL being accessible and appropriate AUTH_USER property set to my domain account name) => no problem here.
2) When accessing any URL matching URL rewrite pattern, e.g. "hostname/foo" the result is:
HTTP Error 401.1 - Unauthorized
You do not have permission to view this directory or page using the credentials that you supplied.
Module WindowsAuthenticationModule
Notification AuthenticateRequest
Error Code 0x80070055
Requested URL http://hostname/index?x=foo
Physical Path D:\wwwroot\
Logon Method Not yet determined
Logon User Not yet determined
(if we try to access the rewritten URL directly, e.g. hostname/index?x=foo, Kerberos works again normally)
The attempts to solve it so far:
After googling, we have tried several options:
turning kernel mode ON: Kerberos stopped working completely, using either default pool identity or network service (I suppose we would need to setup additional HTTP SPN and/or use custom domain account with additional SPN for that account explicitly)
turning "useAppPoolCredentials" ON: no difference
enabling "Failing Request Tracing": surprisingly these failing 401.1 requests ARE NOT generating any output into the fail logs no matter what rule we try to setup (e.g. 400-999) - the folder is just empty (while other errors, like 404 or even handshake 401.x when accessing not-rewritten URLs are generating logs - very strange)
The conclusion:
So far we have reached a dead end - it may be some weird kind of "double hop" issue requiring using a custom domain account rather than default app pool identity, but as we're in fact accessing the same resources, it seems more like a URL Rewrite issue.
Any tips, hints, pointers? Anything would be highly appreciated.
Best regards,
Marek
we face the same issues as you do. By enabling extended error logging, we were able to put the finger on the actual problem, which seems to be a bug in the rewrite module (or at least in some part of IIS, which is related to the module):
When the URL gets rewritten, the access to the new rewritten URL is checked (seemingly hardcoded) using Basic Authentication and NTLM, neither of which has been configured on the Website at hand. The only configured authentication provider is Kerberos. Since the client doesnt send NTLM nor Basic credentials, there is no way this can work.
We (another person on the current project) are sending the issue to Microsoft. I will let you know, when I get any result.
It seems as though you have multiple issues here.
Failed-Request Tracing Logs
To fix your missing logs issue, you must make sure that the user that is running your site's AppllicationPool has read/modify rights to the folder where those logs are generated, otherwise you won't see anything. See the section labeled "Enable Failed-Request Tracing" on this page: Troubleshoot Failed Requests Using Tracing in IIS 7
What isn't clear is the fact that the site's Application Pool Identity (found in Advanced Settings for Application Pool) is the account that needs read/modify rights to that folder.
Once that is fixed you can load the XML logs in IE and see a much clearer picture of what is going on.
401.1 - Unauthorized Issue
A possible fix to your 401 error is to make sure unlisted file name extensions are allowed in Request Filtering. Go to IIS --> Sites --> [your site] --> Request Filtering
You have two options here:
Allow File Name Extension... and add the value "." (minus the quotes), see this answer.
Edit Feature Settings... and enabled the option "Allow unlisted file name extensions"
The 1st option should work well, the 2nd option obviously opens up a gaping hole but allows everything so you should be able to get it working.
I hope that helps.

Server - Windows 2K8/IIS7/ColdFusion throwing intermittent 403 errors

We've just set up a new dedicated server at hostgator, running Windows 2008 Server, IIS7 and ColdFusion 8 ENT.
On browsing the homepage, sometimes the site works, sometimes, part of the site runs and I can see a 403 error in Firebug. At other times, I only get an IIS error page saying:
"403 - Forbidden: Access is denied. You do not have permission to view this directory or page using the credentials that you supplied."
The site is http://www.asia-buy.com. It might run first time, but if you refresh it a few times, you'll probably encounter the problem.
There is a lot of ajax and JSON stuff going on under the hood and I'm wondering if that has any bearing on the problem.
Would appreciate advice from anyone who may have solved a similar issue in the past.
Resolved: Hostgator says this is actually a security setting in IIS to attempt to prevent DDOS attacks on the website. A a developer, I use CTRL-F5 a lot. A normal user would not.
Full error:
HTTP Error 403.502 - Forbidden
The IP address from which you are browsing is not permitted to access the requested Web site because it has made too many requests over short period of time.
Open IIS Manager.
Go to your website.
Go to Features/IP Address and Domain Restrictions/Dynamic IP Restriction Settings
Uncheck the boxes, or change the values, as needed

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