Hi!
I implemented a ssh conection from the outside to my intranet. This ssh requires a username and a password.
In terms of security what is more secure: require authentication (username and password) or having the public key of each user that connects to our intranet in the
authorized public key lists (in this case there is no need for username and password)?
In the second case there is no need of authentication and only the users wich have the public keys in the list are allowed to enter in my intranet.
This second solution is a good solution or that brings other security problems ?
Thanks.
--
Farewell.
"Keep your friends close, but your enemies closer."
"Do or do not. There is no try" - Yoda
João Reis
-------------------------------------------------------
Hi,
>I have just read an Bell Labs anouncement, that they are going to release
>libsafe under GNU licence, and that some major Linux distros are going to
>be using it. SuSE was not amongst them, why is that? I think that libsafe would
>be a good echnacement against buffer overflow.
>
>Anouncement is on:
>http://www.bell-labs.com/news/2000/april/20/1.html
just because something new pops up please be careful with questions like
"when will you implement it?" ;-)
There are several questions to ask:
a) is it STABLE and does it NOT affect the stability of other programs?
b) does it bring additional security problems into the system?
c) is the security protection effective?
Well, of course the SuSE Security Team already reviewed libsafe.
Here are the answers:
a) unsure. it would have to be tested very intensive. this was not done yet.
b) the code might have vulnerabilities, however the protection gained is
higher even if a vulnerability would be present
c) okay, now the tough part:
libsafe is a dynamic library which is set in the environment which checks
several dangerous functions, which can be a security problem.
Because it is a dynamic library, it is NO protection against local
attackers, just against remote attackers on network services. (if an
attacker wants to attack a local suid file, he would just reset his library
path environment). Next thing: it does not check for all known
vulnerabilites. It even doesn't protect against all buffer overflows, It
just protects against *some* overflows. those which happen because of
insecure use of strcat/strcpy etc.
summary:
I can not remember a vulnerability in a network service for the last year
which this tool would have prevented. Therefore: as long as this tool is not
enhanced to also protect open/fopen calls against symlink/hardlink/pipe
attacks, several more buffer overflow types, system/exec* function
protection etc. it is not useful to use this tool.
I would rather propose to use the secumod module which comes with SuSE Linux
since 6.3 and maybe the secure-linux kernel patch from www.openwall.com -
these two tools enhance your security. (and btw, install seccheck,
hardensuse and firewals and use them - then your security is very high)
Greets,
Marc
--
Marc Heuse, SuSE GmbH, Schanzaeckerstr. 10, 90443 Nuernberg
E@mail: marc(a)suse.de Function: Security Support & Auditing
"lynx -source http://www.suse.de/~marc/marc.pgp | pgp -fka"
Key fingerprint = B5 07 B6 4E 9C EF 27 EE 16 D9 70 D4 87 B5 63 6C
I must be able to telnet from a terminal (not a console) as a root without
using su.
In solaris i could do that editing /etc/default/login file,but i can't find
it on this
Operating System.
How can i do ?
Thanks
-----BEGIN PGP SIGNED MESSAGE-----
______________________________________________________________________________
SuSE Security Announcement
Package: netscape
Announcement-ID: SuSE-SA:2000:48
Date: Thursday, November 30th, 2000 19:00 MET
Affected SuSE versions: 6.0, 6.1, 6.2, 6.3, 6.4, 7.0
Vulnerability Type: clientside remote vulnerability
Severity (1-10): 4
SuSE default package: yes
Other affected systems: systems w/ netscape versions before 4.76
Content of this advisory:
1) security vulnerability resolved: netscape
problem description, discussion, solution and upgrade information
2) pending vulnerabilities, solutions, workarounds
3) standard appendix (further information)
______________________________________________________________________________
1) problem description, brief discussion, solution, upgrade information
Michal Zalewski <lcamtuf(a)DIONE.IDS.PL> has found a buffer overflow in
the html parser code of the Netscape Navigator in all versions before
and including 4.75. html code of the form
<form action=foo method=bar>
<input type=password value=long string here>
more form tags
</form>
can crash the browser. It may be possible for an attacker to supply
a webpage that executes arbitrary code as the user running netscape.
As of today, no exploit code is known to exist in the wild.
SuSE provides an update package for the vulnerable software. It is
recommended to upgrade to the latest version found on our ftp server
as described below. The update package introduces Netscape version
4.76.
NOTE:
Please note that Netscape-4.76 is not available for the glibc-2.0-based
SuSE Distributions SuSE-6.0 and 6.1 because Netscape doesn't provide
any binaries for the glibc version in these distributions (glibc-2.0).
For SuSE-6.0 and 6.1, we provide a libc5-based version of netscape-4.76
which runs smoothly on all i386-based SuSE distributions 6.x and 7.x,
provided the package shlibs5 is installed. The package can be found in
the update/5.3 directory on our ftp server (see below).
There are no packages available for platforms other than i386.
NOTE:
The packages on our ftp servers date back to October 31st. Since
there is no release notes or README file with equivalent content
in the netscape tarball, SuSE security was not aware of the fact
that this release of netscape fixes the known problems. This
information can be obtained from (along with information about
other bugfixes)
http://home.netscape.com/eng/mozilla/4.7/relnotes/windows-4.76.html .
Please choose the update package(s) for your distribution from the URLs
listed below and download the necessary rpm files. Then, install the
package using the command `rpm -Uhv file.rpm´. rpm packages have an
internal md5 checksum that protects against file corruption. You can
verify this checksum using the command (independently from the md5
signatures below)
`rpm --checksig --nogpg file.rpm',
The md5 sums under each package are to prove the package authenticity,
independently from the md5 checksums in the rpm package format.
Intel i386 Platform
SuSE-7.0
SuSE-6.4
SuSE-6.3
SuSE-6.2
ftp://ftp.suse.com/pub/suse/i386/update/7.0/xap1/netscape-4.76.glibc21.i386…
7ccebaca7df0937a3c08fc30a27af858
SuSE-6.1
SuSE-6.0
ftp://ftp.suse.com/pub/suse/i386/update/5.3/xap1/netscape-4.76.libc5.i386.r…
3c4f06c5fea4755083524eb135627380
______________________________________________________________________________
2) Pending vulnerabilities in SuSE Distributions and Workarounds:
- ssh/openssh
Several inconsistencies and configuration bugs have been introduced
in the SuSE rpm packages for the update of openssh (SuSE-SA:2000:47)
that cause the openssh software to not work as reliably as usual.
The packages are about to be reworked, the openssh announcement will
be reissued.
- pidentd
The in.identd daemon on SuSE distributions can be crashed remotely.
We're working on a fix.
- bash1
bash, version 1, handles temporary files in an unsafe manner that
allows a local attacker to overwrite arbitrary files as the user
running a bash1 with input redirection of the "<< EOF" style.
The bash1 package is not used per default in SuSE-distributions.
We're working on a fix (update packages).
- tcsh
The paragraph above about bash version 1 applies to the tcsh as
well, in all versions. The tcsh is not used by SuSE scripts.
______________________________________________________________________________
3) standard appendix:
SuSE runs two security mailing lists to which any interested party may
subscribe:
suse-security(a)suse.com
- general/linux/SuSE security discussion.
All SuSE security announcements are sent to this list.
To subscribe, send an email to
<suse-security-subscribe(a)suse.com>.
suse-security-announce(a)suse.com
- SuSE's announce-only mailing list.
Only SuSE's security annoucements are sent to this list.
To subscribe, send an email to
<suse-security-announce-subscribe(a)suse.com>.
For general information or the frequently asked questions (faq)
send mail to:
<suse-security-info(a)suse.com> or
<suse-security-faq(a)suse.com> respectively.
===============================================
SuSE's security contact is <security(a)suse.com>.
===============================================
Regards,
Roman Drahtmüller.
- - --
- -
| Roman Drahtmüller <draht(a)suse.de> // "Caution: Cape does |
SuSE GmbH - Security Phone: // not enable user to fly."
| Nürnberg, Germany +49-911-740530 // (Batman Costume warning label) |
- -
______________________________________________________________________________
The information in this advisory may be distributed or reproduced,
provided that the advisory is not modified in any way.
SuSE GmbH makes no warranties of any kind whatsoever with respect
to the information contained in this security advisory.
Type Bits/KeyID Date User ID
pub 2048/3D25D3D9 1999/03/06 SuSE Security Team <security(a)suse.de>
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Hi,
my name is Chris and I just started using LINUX.
Now my problem I have to install a very save server.
The server should work as a file-server which is also WWW-router,
firewall and Mailserver for a network of 25 workstations with Windows
NT.
5 Days ago I started working in LINUX but my employer wants me to create
a server that is saver than a very save NT-system.
I'm not able to create such a system by myself!! Please Help me
Greetings Chris
Hi,
after reading the last security-announcement I ask myself if there is a tool to
update the new rpm automatically to all the boxes in my LAN.
What I want to do
is the following:
I recieve the security-announcement:
I decide to install or not and download the rpm.
I start a script, which will install the rpm to the boxes of my choice.
I don't want to login on every box, install the rpm and go to the next box.
I hoped alice would do things like that, but I think alice is only a tool for
new installation (and you have to make a floopy-disk or a CD).
And I think, some month ago, I have read about a scripting-language for system
administrators, but I don't remember where.
Anybody, who can help me.
Hello Thom
Am Don, 30 Nov 2000 schrieb Thorsten Marquardt:
> Hello Magus
>
> Am 30-Nov-00 schrieb Magus Ba'al:
>
> > I got this from http://www.proftpd.net/docs/complex-virtual.conf
> >
> > AuthUserFile /where.ever.you.want.to.stick.it
> > AuthGroupFile /where.ever.you.want.to.stick.it
> >
> > What _I_ prefer to do is create a directory, let's call it /var/domains.
> > Because I host multiple domains, I put the auth files in /var/domains with
> > the name , and then create a dir in /var/domain/(domain name). It keeps it
> > neat and tidy for me if I ever need to find anything related to the
> > domain.
>
> so far so good. But I don't know how to create the AuthUserFile itself.
>
why don't you use the program 'htpasswd', afaik it's delivered with apache.
htpasswd makes a file with a username&password-File. this files contains in
each line one user. It's build like the /etc/passwd:
username:passwd:uid:gid:comments:Home-dir:shell
but with htpasswd, you've only the 1st and 2nd entry, the others have to be
edited by you.
that's the way I do it...
Max
Hello:
Im a newbie at Linux. Recently setup a SuSE 7.0 LinUx box and had
everything going well. Until, I made a few changes in the /etc/rc.config
and somehow disabled my FTP Services. I've also made changes in my
etc/rc.config.d/firewall.rc.config too and now I totally blocked out of my
ftp services. I know I'm not being clear on the info I've given but can
anyone help me get started with re-enabling ftp services again.
Is it?
start Inetd="yes"??
start Proftpd="yes"????
Thanks,
___________________________
Pao Sayaovang
Weyco Group, Inc
DID(414) 908~1813
Fax(414) 908~1913
psayang(a)weycogroup.com
Hi,
I need to install a nntp proxy on my suse 6.3, and I tried acmennrp. When I
start it, it justs stops without a single (error) message; I bet there is
something missing. Since I cannot read java (sorry),and cannot find a clue
of a documentation neither any logged message anywhere (yes, syslogd is
configured and working all right), what else can I do ? Does anybody knows
about using acmennrp (proxy mode only), or any other SW that woul do it ?
Thanks,
Olivier.
------------------------------------------------------------------------------------------------
Olivier Hislaire
MSG International Email: O.Hislaire(a)msg-i.com
97 Avenue de Tervuren Phone: +32 (0)2 735.91.59 Ext. 55
1040 Brussels Fax: +32 (0)2 732.12.19
Belgium http://www.msg-i.com
------------------------------------------------------------------------------------------------
