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Date: Thu, 20 Jun 2002 09:41:05 -0700 (PDT)
From: aeonflux <aeonflux@trioptimum.com>
To: freebsd-gnats-submit@FreeBSD.org
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Subject: conf/39580: insecure default settings
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>Number:         39580
>Category:       conf
>Synopsis:       insecure default settings
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Thu Jun 20 09:50:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     aeonflux
>Release:        4.6 release
>Organization:
none
>Environment:
4.6 release
>Description:
By default in the install, when you have label create the drive partitions for you, a /tmp label is created however it is not mounted with the options "nofollowsymlinks" which would help stop race conditions.

As well, /tmp is not mounted with nosuid, allowing suid bit binaries to execute from the tmp directory.

Further reading from Kris Kennaway
http://old.lwn.net/2000/1221/a/sec-tmp.php3

>How-To-Repeat:
exploit any race condition, like the adobe pdf writer one for example.
symlink a preditable file in /tmp to /etc/master.passwd, etc...  you all know the drill.
>Fix:
edit /etc/fstab after installation and change the options to
"rw,nosymfollow,nosuid"

alter sysinstall to make those options default.
>Release-Note:
>Audit-Trail:
>Unformatted:

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