[SOLVED] Microsoft Exchange Authentication Error: No HOST

asked 2016-08-01 04:47:49 +0200

AfanO
1 ●1 ●1 ●4

updated 2016-08-01 13:50:36 +0200

Had a client who had difficulty authenticating to an Exchange Server via HTTPS behind an ssl proxy server.

The error that was generated on thier jolla phone (2.0.1.11) was

Problem with Checking Credentials: Could not authenticate account

( I can't upload the actual screenshot they sent due to karma < 10)

In investigating the raw traffic between the phone and the server it became clear that the HTTP traffic from the phone did not include the HOST header. So the proxy server could not determine to which server the SSL traffic should be delivered.

This bug would affect any large organization that uses for their Exchange servers:

• SSL Load ballancer
• SSL Proxy Services
• Multiple SSL sites per machine/ virtualaization etc.
• Most Cloud services configurations.

The workaround we discovered was to add this line to the haproxy.cfg file:

acl host_REDACTED url_beg /Microsoft-Server-ActiveSync

But the REAL solution should be that the phone should follow the HTTP 1.1 protocols and include the HOST header.