Login
Newsletter
Werbung

Sicherheit: Pufferüberlauf in ncurses
Aktuelle Meldungen Distributionen
Name: Pufferüberlauf in ncurses
ID: SuSE-SA:2000:043
Distribution: SUSE
Plattformen: Keine Angabe
Datum: Fr, 27. Oktober 2000, 13:00
Referenzen: Keine Angabe
Applikationen: ncurses

Originalnachricht

--168455424-1317636801-972662386=:18975
Content-Transfer-Encoding: 8BIT

-----BEGIN PGP SIGNED MESSAGE-----

______________________________________________________________________________

SuSE Security Announcement

Package: ncurses
Announcement-ID: SuSE-SA:2000:043
Date: Friday, October 27th, 2000 17:00 MEST
Affected SuSE versions: 6.0, 6.1, 6.2, 6.3, 6.4, 7.0
Vulnerability Type: local root compromise
Severity (1-10): 5
SuSE default package: yes
Other affected systems: systems with suid binaries linked against
ncurses

Content of this advisory:
1) security vulnerability resolved: ncurses
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

The ncurses library is used by many text/console based applications
such as mail user agents, ftp clients and other command line utilities.
A vulnerability has been found by Jouko Pynnönen <jouko@solutions.fi>
in the screen handling functions: Insufficient boundary checking leads
to a buffer overflow if a user supplies a specially drafted terminfo
database file. If an ncurses-linked binary is installed setuid root,
it is possible for a local attacker to exploit this hole and gain
elevated privileges.

There are several ways to fix the problem associated with the library.
One of them would be to fix the library. However, it is not considered
unlikely that another problem (similar to the one that has just been
found) will be revealed in the future. Therefore, it is advisable to
not link setuid applications against the ncurses library. As a permanent
and cleaner fix, we do not provide update packages for the ncurses
library, but we suggest to change the modes of the relevant setuid
applications. There are three setuid-root applications contained in
SuSE-distributions:
xaos (suid root for permissions to use SVGAlib on the Linux console)
screen (does not need root privs in the latest version)
cda, contained in the xmcd program, a command line CD player. It might
need elevated privileges to access the cdrom device file.

The script attached to the email with this announcement changes the
modes of files in the SuSE distribution that match both criteria
necessary to exploit the buffer overflow in the ncurses library:
1) the binary is setuid root,
2) it is linked against libncurses.
Please save the attachment under the name "perms-ncurses.sh" and
execute it using the command `bash ./perms-ncurses.shŽ.
It does:
a) Check your version of the screen program installed.
b) Changes /etc/permissions and /etc/permissions.easy to reflect
the mode changes. The original files are saved, see
/etc/permissions.* . (note: The chkstat program is being
executed by SuSEconfig, the SuSE configuration script, to set
the modes of files according to the entries in the permission
files. The files being used are /etc/permissions,
/etc/permissions.local and /etc/permissions.easy unless the
administrator changed the settings in /etc/rc.config .)
c) Changes the file modes by hand by executing
chmod 755 /usr/X11R6/lib/X11/xmcd/bin-Linux-$ARCH/cda \
/usr/bin/screen /usr/bin/xaos

You can download the script from the following location:

ftp://ftp.suse.com/pub/suse/noarch/perms-ncurses.sh
md5sum:
abe22607d45ecdb710f6061d5bbd3d13

______________________________________________________________________________

2) Pending vulnerabilities in SuSE Distributions and Workarounds:

A summary about ongoing issues will be included in the next security
announcement.
______________________________________________________________________________

3) standard appendix:

SuSE runs two security mailing lists to which any interested party may
subscribe:

suse-security@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@suse.com>.

suse-security-announce@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@suse.com>.

For general information or the frequently asked questions (faq)
send mail to:
<suse-security-info@suse.com> or
<suse-security-faq@suse.com> respectively.

===============================================
SuSE's security contact is <security@suse.com>.
===============================================

Regards,
Roman Drahtmueller.
--
- -
| Roman Drahtmueller <draht@suse.de> // "Caution: Cape
does |
SuSE GmbH - Security Phone: // not enable user to fly."
| Nuernberg, 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@suse.de>

-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: 2.6.3i

mQENAzbhLQQAAAEIAKAkXHe0lWRBXLpn38hMHy03F0I4Sszmoc8aaKJrhfhyMlOA
BqvklPLE2f9UrI4Xc860gH79ZREwAgPt0pi6+SleNFLNcNFAuuHMLQOOsaMFatbz
JR9i4m/lf6q929YROu5zB48rBAlcfTm+IBbijaEdnqpwGib45wE/Cfy6FAttBHQh
1Kp+r/jPbf1mYAvljUfHKuvbg8t2EIQz/5yGp+n5trn9pElfQO2cRBq8LFpf1l+U
P7EKjFmlOq+Gs/fF98/dP3DfniSd78LQPq5vp8RL8nr/o2i7jkAQ33m4f1wOBWd+
cZovrKXYlXiR+Bf7m2hpZo+/sAzhd7LmAD0l09kABRG0JVN1U0UgU2VjdXJpdHkg
VGVhbSA8c2VjdXJpdHlAc3VzZS5kZT6JARUDBRA24S1H5Fiyh7HKPEUBAVcOB/9b
yHYji1/+4Xc2GhvXK0FSJN0MGgeXgW47yxDL7gmR4mNgjlIOUHZj0PEpVjWepOJ7
tQS3L9oP6cpj1Fj/XxuLbkp5VCQ61hpt54coQAvYrnT9rtWEGN+xmwejT1WmYmDJ
xG+EGBXKr+XP69oIUl1E2JO3rXeklulgjqRKos4cdXKgyjWZ7CP9V9daRXDtje63
Om8gwSdU/nCvhdRIWp/Vwbf7Ia8iZr9OJ5YuQl0DBG4qmGDDrvImgPAFkYFzwlqo
choXFQ9y0YVCV41DnR+GYhwl2qBd81T8aXhihEGPIgaw3g8gd8B5o6mPVgl+nJqI
BkEYGBusiag2pS6qwznZiQEVAwUQNuEtBHey5gA9JdPZAQFtOAf+KVh939b0J94u
v/kpg4xs1LthlhquhbHcKNoVTNspugiC3qMPyvSX4XcBr2PC0cVkS4Z9PY9iCfT+
x9WM96g39dAF+le2CCx7XISk9XXJ4ApEy5g4AuK7NYgAJd39PPbERgWnxjxir9g0
Ix30dS30bW39D+3NPU5Ho9TD/B7UDFvYT5AWHl3MGwo3a1RhTs6sfgL7yQ3U+mvq
MkTExZb5mfN1FeaYKMopoI4VpzNVeGxQWIz67VjJHVyUlF20ekOz4kWVgsxkc8G2
saqZd6yv2EwqYTi8BDAduweP33KrQc4KDDommQNDOXxaKOeCoESIdM4p7Esdjq1o
L0oixF12Cg==
=pIeS
-----END PGP PUBLIC KEY BLOCK-----

-----BEGIN PGP SIGNATURE-----
Version: 2.6.3i
Charset: noconv

iQEVAwUBOfmlFXey5gA9JdPZAQG+HQf9GQ2b3bGulr6WZKOhHxLbl71Nj7dI+ord
rI8g1/sC0ie+FdjTz0A796CrnUBEh/NwgrOltvXaQXhiTzQguPqnpgoEvct8YF06
tDzCbMog9Jq11Q+YeWRdXbpODqumYoNZdni4gyCWbz391ADi4rlIuhM9yjOkIbHU
8qmvhXS2OvKLNxKM53JX/dWnwrFNvd7sdvrnUMKfga23AEM923LLfq94a7WZtXHg
42nHySQiwrn7l37Zbu+IDeQ5/PQw3MU3AfS1Hhhuofoa6ot8do3mCDO9R6CvDxlg
980AfBGHrDd6l8Wf9g5/+lxKtS641a8sbzzasmAFI2vHGL5KQbt6DA==
=Jd2C
-----END PGP SIGNATURE-----

--168455424-1317636801-972662386=:18975
Content-Transfer-Encoding: BASE64
Content-ID: <Pine.LNX.4.21.0010271759460.18975@dent.suse.de>
Content-Description: perms-ncurses.sh
Content-Disposition: attachment; filename="perms-ncurses.sh"
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--168455424-1317636801-972662386=:18975

--
To unsubscribe, e-mail: suse-security-announce-unsubscribe@suse.com
For additional commands, e-mail: suse-security-announce-help@suse.com
--168455424-1317636801-972662386=:18975--
Pro-Linux
Traut euch!
Neue Nachrichten
Werbung