Linux-Mandrake Security Update Advisory: glibc update

Date: Wed, 6 Sep 2000 22:26:09 -0600
From: Linux Mandrake Security Team security@LINUX-MANDRAKE.COM

Subject: MDKSA-2000:045 – glibc update

                Linux-Mandrake Security Update Advisory

Package name:           glibc
Date:                   September 6th, 2000
Advisory ID:            MDKSA-2000:045

Affected versions:      7.0, 7.1

Problem Description:

A bug was discovered in ld.so that could allow local users to
obtain root privileges. The dynamic loader, ld.so, is responsible
for making shared libraries available within a program at run-time.
Normally, a user is allowed to load additional shared libraries
when executing a program; they can be specified with environment
variables such as LD_PRELOAD. Because this is not acceptable for
applications that are setuid root, ld.so normally removes these
environment variables for setuid root programs. The discovered bug
causes these environment variables to not be removed under certain
circumstances. While setuid programs themselves are not vulnerable,
external programs they execute can be affected by this problem.

A number of additional bugs have been found in the glibc locale
and internationaliztion security checks. In internationalized
programs, users are permitted to select a locale or choose message
catalogues using environment variables such as LANG or LC_*. The
content of these variables is then used as part of the pathname
used to search message catalogues or locale files. Under normal
circumstances, if these variables contained the “/” character, a
program could load the internationalization files from arbitrary
directories. This is not acceptable for setuid programs, which is
the reason glibc does not allow certain settings of these variables
if the program is setuid or setgid. However, some of these checks
were done in inapporpriate places, contained bugs, or were missing
entirely. It is highly probable that some of these bugs can be used
for local root exploits.

Please verify these md5 checksums of the updates prior to
upgrading to ensure the integrity of the downloaded package. You
can do this by running the md5sum program on the downloaded package
by using “md5sum package.rpm”.

Linux-Mandrake 7.0:

Linux-Mandrake 7.1:

To upgrade automatically, use « MandrakeUpdate

If you want to upgrade manually, download the updated package
from one of our FTP server mirrors and uprade with “rpm -Uvh

You can download the updates directly from:



Or try one of the other mirrors listed at:


Updated packages are available in the “updates/[ver]/RPMS/”
directory. For example, if you are looking for an updated RPM
package for Linux-Mandrake 7.1, look for it in “updates/7.1/RPMS/”.
Updated source RPMs are available as well, but you generally do not
need to download them.

Please be aware that sometimes it takes the mirrors a few hours
to update, so if you want an immediate upgrade, please use one of
the two above-listed mirrors.

You can view other security advisories for Linux-Mandrake


If you want to report vulnerabilities, please contact


Linux-Mandrake has two security-related mailing list services
that anyone can subscribe to:


Linux-Mandrake’s security announcements mailing list. Only
announcements are sent to this list and it is read-only.


Linux-Mandrake’s security discussion mailing list. This list is
open to anyone to discuss Linux-Mandrake security specifically and
Linux security in general.

To subscribe to either list, send a message to sympa@linux-mandrake.com with
“subscribe [listname]” in the body of the message.

To remove yourself from either list, send a message to sympa@linux-mandrake.com with
“unsubscribe [listname]” in the body of the message.

To get more information on either list, send a message to
sympa@linux-mandrake.com with
“info [listname]” in the body of the message.

Optionally, you can use the web interface to subscribe to or
unsubscribe from either list:


Get the Free Newsletter!

Subscribe to Developer Insider for top news, trends, & analysis