dont throw for no WwwAuthenticateHeader in Challenge result (#4542)

AzureAD · Jan 24, 2024 · d01b12d · d01b12d
1 parent 366418e
commit d01b12d
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/client/Microsoft.Identity.Client/PlatformsCommon/Shared/DeviceAuthHelper.cs b/src/client/Microsoft.Identity.Client/PlatformsCommon/Shared/DeviceAuthHelper.cs
@@ -18,7 +18,7 @@ public static IDictionary<string, string> ParseChallengeData(HttpResponseHeaders
         {
             IDictionary<string, string> data = new Dictionary<string, string>();
             string wwwAuthenticate = responseHeaders.GetValues(PKeyAuthConstants.WwwAuthenticateHeader).SingleOrDefault();
-            wwwAuthenticate = wwwAuthenticate.Substring(PKeyAuthConstants.PKeyAuthName.Length + 1);
+            wwwAuthenticate = wwwAuthenticate?.Substring(PKeyAuthConstants.PKeyAuthName.Length + 1);
             if (string.IsNullOrEmpty(wwwAuthenticate))
             {
                 return data;