#717158 network-manager: ignores settings from dhclient.conf and requests insecure properties

Package:
network-manager
Source:
network-manager
Description:
network management framework (daemon and userspace tools)
Submitter:
Christoph Anton Mitterer
Date:
2022-06-18 19:15:03 UTC
Severity:
normal
Tags:
#717158#5
Date:
2013-07-17 12:54:04 UTC
From:
To:
Hi.

NM aparently thinks it's smarter and ignores any settings from dhclient.conf.
This leads to security problems, if one e.g. intentionally told dhcp
to ignore properties like the dns-search path, which may be used by a hostile
dhcp server to trick you into wrong domains.

Chris.
#717158#18
Date:
2013-07-17 19:15:22 UTC
From:
To:
* Christoph Anton Mitterer:

dhclient.conf only controls which options are requested from the
server, the client will process unsolicited options anyway.
Therefore, changing dhclient.conf adds zero additional security.

Upstream provided means to fix this in ISCP DHCP 4.2.5, but it
requires adjustments to our DHCP response handling script.
#717158#23
Date:
2013-07-17 19:55:22 UTC
From:
To:
Am 17.07.2013 21:15, schrieb Florian Weimer:

Fwiw, I had already removed the security tag

Michael
#717158#28
Date:
2013-07-18 21:30:40 UTC
From:
To:
I see... how does this work than? Can I really choose which settings I
want and which not... and does this fix the problem then at both places,
dhcp itself and NM?


Cheers,
Chris.