System.FormatException on every Request

[JackSteel97]

Problem

This exception occurs, as far as I can tell, every time the server receives a request to any of the endpoints. It does not fall out to any of my catchs and the program does not crash, the only way I know it happens is the Event log in visual studio shows the below:

Clicking through to Historical Debugging does not provide much useful info either:

The only thing resembling a call stack I can find is in the debug output:

Since it is not breaking anything in my program it isn't a major issue, but it would be nice to know why it's happening; if it's something obscure I've done wrong or a bug in ASP.NET.

If anyone has any troubleshooting suggestions please let me know, if not I will try and get a repo with a repro project up at some point.

dotnet --info output

.NET Core SDK (reflecting any global.json):
Version: 2.1.402
Commit: 3599f217f4

Runtime Environment:
OS Name: Windows
OS Version: 10.0.17134
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\2.1.402\

Host (useful for support):
Version: 2.1.4
Commit: 85255dde3e

.NET Core SDKs installed:
1.1.10 [C:\Program Files\dotnet\sdk]
2.1.202 [C:\Program Files\dotnet\sdk]
2.1.400 [C:\Program Files\dotnet\sdk]
2.1.401 [C:\Program Files\dotnet\sdk]
2.1.402 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
Microsoft.AspNetCore.All 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 1.0.12 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 1.1.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.3-servicing-26724-03 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]

[Tratcher]

Looks like a problem with your session cookie. Have you tried clearing your browser cookies?

If you capture the value first we can see what might be wrong with it.

@Tratcher For context, we run ADFS at our institution. When a user signs in, we add some additional (service specific) claims into the claims principal for the session using the following method in a helper class:

public static async Task AddClaims(HttpContext context, Claim[] claimsToAdd)
{
    // Clone the ADFS claims principal.
    ClaimsPrincipal clonedClaimsPrincipal = context.User.Clone();

    // Add new claims to the cloned ClaimsIdentity.
    foreach (Claim claim in claimsToAdd)
    {
        ((ClaimsIdentity)clonedClaimsPrincipal.Identity).AddClaim(claim);
    }

    // Sign out, clearing the original cookie set by ADFS.
    await context.SignOutAsync(CookieAuthenticationDefaults.AuthenticationScheme);

    // Sign in with the cloned claims principal, recreating the cookie.
    await context.SignInAsync(CookieAuthenticationDefaults.AuthenticationScheme, clonedClaimsPrincipal);
}

I don't know if something we're doing here would be causing the issue?

[Tratcher]

No, it's your browser session cookie that looks broken, not your user auth cookie.

Thanks for confirming :)

[JackSteel97]

I have cleared all browser cookies and tried again. I noticed that the error is only thrown on requests when I am signed in, and on the request to sign in. From the looks of it, the only cookie available after the error is thrown is the one used for authentication. I am not using any session storage so that would make sense.

[Tratcher]

Please share the request headers.

[JackSteel97]

@Tratcher
:authority: localhost:44357
:method: GET
:path: /routing/routerequest?startNode=cthirteen&endNode=csb&accessibleRoute=false&routeType=b2b&startType=Normal%20Start
:scheme: https
accept: application/json
accept-encoding: gzip, deflate, br
accept-language: en-US,en;q=0.9,en-GB;q=0.8
content-type: application/json
cookie: _ga=GA1.1.421663564.1537863656; _gid=GA1.1.1347427406.1537863656; navigateme.lincoln.ac.uk=CfDJ8IjkMt7WS49OmVKhOwTUR1-FhCoVhQL6bH-_lVpvkdZt-0TIHAXcow-8FcVJXbel0AF80Ol0-CzGnllskzd2ExwsX00hj1vd6_dOkzIVTLTqG3NRfjcHW2HAbQgYHn-pi7BXSZFcB5iC00kqDErKP1r6MGnH9dbIAZcYLNCJGb-VClPdNi4ZeXycan533YqO3oQf99GqPaD8dzylSXqhar47lQozDyMzsPgjRb91d7w_4Rf6WyQwfi0Cw2Ygk80xQBMPZrEkBYR9ZU0i9Y9jcSIuX0_ApbUO9td0bSwyaWaC3aycaX5Qq0yjFRm08gALc8P_sYyl1PpvOanzezU58LkjOK78PzheFdaUsH3sO_SYC5061VYEfLEgw-NTUWUhGVkWAc7GtbL4ZKufLR4WFXRc4Dx5FcIA_0QDUKiF1i6XNVMTKa_CgXgagRFFROGrhA2zhNYccgYjhsnER-P4Xqz5ZVdWqp1AZ_cOxgAoLgHkaGrCbZgUz_TmzXKfqoADoHFeWxndlr-pTq1Fdr0RNIKTt_Jt7svNQtTr-Hux-8bj9YX7oSBkDMmU6NFCSELbRSuZic14_MWtapVDxeywG0wU5k40VbBzZ2sW_kQiQxrvd49jIODyEurTb8kh4JERFGr0aj2g4uucPmXnhnsWHNfnJzb2BRj0D3fygiESihPaKvOZYbHVhk3pmtpRTJQyOh_R05lN5iMQ8LibLV83FQyyjsPIEIbs7l4UPIuQNeu5qXUNSqjok4Gpg4Uk5UHN05NA_e4Mfm7F0fMW5nuXC6gAHcYciaxkZSNkU-gIbHKmveOOd1p_3j3FyPu6kPjlheY_w0TuDSchusOP7o_B24I6GLcQ3uOeQpwC7YGADU6F_1aqZcXNysG58BKELetUjVA7Xrah9br_vzL-HPJcVbZRms-ncbnQxlqAnMcqHurg7Gm8oMrNOqD3knVqJWAIEeBcCBhpUOemxMdNYKqYrlEFTHCK86pZKWleUyHs1knjqZkvePIzPCBbvokR720n5YDOSv6WyEDtk5OFwBdoXGDpyRJYOmmKdJUza7AsgBc71tKLKoMJ16W79E9w_H32B7YvpOc4TBFfoWyiFofxqWvZYa1WBBQcAEYnBgJMCR83J1vHM-TTRQ0XamWtYdYfUp_OyXmqPF7VVKfrld21oyXfKABFkVJ0i4iLomgC3KRiIT46LfZ5FbCstRFEH2yKvZU6mSWCAhSkJw2KnulwzkV6-Unow2aAdgA6zJIrSSOIRLgr2-cM9n7rqVc6jlA3NdsZ_S6dK8UA3cQtioRVFFJCnTLBD6qQNiW7Nc12afLDknQFID9hrqWat6WXH81Zi1qCVSpxqJ3DFBqtLgXq_qnUo00sKy2GmAx8CzUskCDvZAQ_mHcZwLXW_R6UF-dbQxBcDzc7r5XaLEpXRcHDegt-_jgP-zShHayQUlfTPqCXycVU6f4hNHba5FrtoU3n75CJJip4gc917HsA2VwXVQa56EqftYZN_SIrvs056U5rG6Pc4yjhUdTTIAiJmLyj5b9fGVqIMo85L4zLnVzf0u6KpNqTp2N9s2xsJIJZwYc6frJNxtfafNDe44THaCAoZd0dazD1ZjCaKAaVp836f2WeqF-m0uKKtExwPAH6rVEchMIj2GFvlR2j7I6tOGHrW1S-_9GcmgDDV6Zv-KE3pvJqpkrzc4eTITBK88Sr3eIFaD3or3f84C_6qbmLWrIicLtma4NtYYzdfI73piKzVxi2EToZMJAlSsFH-eQjt7KRICID6FdEQsL1aXBAvpDAGbTyhsw1MGyDqdd_szMC4gwa8VifTcd4MbCbNP7QJ6BNsYpiuM4mMMwV39jRu8FdUwQqU-f4q8pBDX7TAo6anca74lpVqnkJjqjTfz3Yb54kVEbzmTZjRZr9-sGQ7sugcrodBy-o8p_rlOTHOKOBR4XoRHpu2s520elENR2Mor54HMN7jCt9vkQhVgW0RSYvzMukHeDpKgLMPBgixrKqvi-kOdZOdBSYD8OIb9Ln6e7N9fr_DZHfJdsan__3VqfrZO7rnI_IEVibJIiUWue0waarlynH-HWkXwgBaTNCmP5A5nbr9G07bCwxB5iXYhsseBpQl7Ew0XvkueApY2k8hx1PaVgnxLiO_VgGiI3DVbKpCNthuod1g0tlbQpN18CZxov39svrff-eew3U_zjeDVC71Wo-6VKrAJharR6eKlrxwmJbCOq60kxks5TO-cZvZwD2-9nlrDAM5-fw-mKM7Yz72db4-jp7tRghlhovofe2bKTLdiLwHgkiYSXr-HOxNeharTWAw35yURXapE2jRYl5GSI1mgbZ8kphfHOfvYW0r5rZuTxhV-3LzE4T0BXHmZT3-Cjbe_JSOJ1aAg2oxk_mJ3aNxuHMaMsg6Yc-vQKDd_fCi0VVh2rdHm4-2NDLi3Z1vKwwIEfjZhlwrfWRxWEmhMmwajdr4yqTF4LJsR-EKhAItipOPoRWkHvGUrsA6qmrAYxXGHrp4Sg89DiWYSGcnr319srZySXPG0aiq31H6QYyDNeELtJwYkA4E1SNyZNp2ik_A2zWKIgCOWbhN96PHNI0iDYjjwEaUUwOB6eQjcms7BkC7-WHffiHtwj3OifdKi1-09MBDkvunbyKf4_4TeQym5osWzlB3GXZTddvc35AL2zo7nJkTsnHv9X76oe9nbYP4gNyD-Yl5_4z2pPsS6dAaE9YCWA2jad-W0qzyQShmQ5NGFfoaZUuHu44gyBZnCJwkv4ObFhAD3fXz0M
referer: https://localhost:44357/?type=s&end=csb&start=cthirteen
user-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36

[Tratcher]

Please don't use screen shots for textual data... Copying the text makes it much easier to examine.

[JackSteel97]

see edit

[Tratcher]

So navigateme.lincoln.ac.uk is the name of your auth cookie? What did you name your session cookie? I don't see any likely matches and the auth cookie looks like valid base64.

[JackSteel97]

... "Application": { "ActiveEnvironment": "development", "Session": { "IdleTimeout": 20, "Cookie": { "Name": "navigateme.lincoln.ac.uk" } }, ...

[Tratcher]

Wait, did you set the name of your auth cookie and your session cookie to the same thing? That's not going to work (though I don't know why it would give this error).

[JackSteel97]

Thanks, that fixed it. Although those cookies have the same name in some other project and this error has never shown up