Bug 41033

Summary:	Set "server signing = mandatory" in smb.conf (Samba/NT)
Product:	UCS	Reporter:	Arvid Requate <requate>
Component:	Samba	Assignee:	Samba maintainers <samba-maintainers>
Status:	RESOLVED WONTFIX	QA Contact:
Severity:	normal
Priority:	P5	CC:	gohmann, grandjean
Version:	UCS 4.2
Target Milestone:	---
Hardware:	Other
OS:	Linux
See Also:	https://forge.univention.org/bugzilla/show_bug.cgi?id=41034 https://forge.univention.org/bugzilla/show_bug.cgi?id=42967 https://forge.univention.org/bugzilla/show_bug.cgi?id=47077
What kind of report is it?:	Security Issue	What type of bug is this?:	---
Who will be affected by this bug?:	---	How will those affected feel about the bug?:	---
User Pain:		Enterprise Customer affected?:
School Customer affected?:		ISV affected?:
Waiting Support:		Flags outvoted (downgraded) after PO Review:
Ticket number:		Bug group (optional):	Security
Max CVSS v3 score:
Bug Depends on:
Bug Blocks:	42045

Description Arvid Requate

2016-04-12 11:12:01 CEST

Without 'ntlm auth = no', there may still be clients not using NTLMv2. The elder original protocol version sends the password hashes across the wire, which may be observed and brute-forced easily. As far as I currently know Samba/AD DCs running 4.3.7 will default to this setting, but for member/file-servers it would be good to adjust the default too.

Comment 1 Arvid Requate

2016-04-12 11:15:05 CEST

We should also consider setting "smb signing = required", which also appears to be default for Samba 4.3.7 AD DCs.

Comment 2 Arvid Requate

2016-04-12 16:32:53 CEST

It's "server signing = mandatory" instead of "smb signing = required".

Comment 3 Arvid Requate

2018-05-29 13:37:56 CEST

*** Bug 47100 has been marked as a duplicate of this bug. ***

Comment 4 Arvid Requate

2018-08-10 19:59:28 CEST

I'm not sure about setting "server signing" explicitly to "mandatory" by default for memberservers. I think we should default to the Samba behavior.

Comment 5 Ingo Steuwer

2020-07-03 20:54:08 CEST

This issue has been filed against UCS 4.2.

UCS 4.2 is out of maintenance and many UCS components have changed in later releases. Thus, this issue is now being closed.

If this issue still occurs in newer UCS versions, please use "Clone this bug" or reopen it and update the UCS version. In this case please provide detailed information on how this issue is affecting you.