Date: Thu, 7 Sep 2000 16:37:00 -0400
From: bugzilla@REDHAT.COM
To: BUGTRAQ@SECURITYFOCUS.COM
Subject: [RHSA-2000:057-04] glibc vulnerabilities in ld.so, locale
and gettext
Red Hat, Inc. Security Advisory
Synopsis: glibc vulnerabilities in ld.so, locale and gettext
Advisory ID: RHSA-2000:057-04
Issue date: 2000-09-01
Updated on: 2000-09-07
Product: Red Hat Linux
Keywords: glibc ld.so locale LANG gettext LD_PRELOAD threads
Cross references: N/A
1. Topic:
Several bugs were discovered in glibc which could allow local
users to gain root privileges.
2. Relevant releases/architectures:
Red Hat Linux 5.0 – i386, alpha
Red Hat Linux 5.1 – i386, alpha, sparc
Red Hat Linux 5.2 – i386, alpha, sparc
Red Hat Linux 6.0 – i386, alpha, sparc
Red Hat Linux 6.1 – i386, alpha, sparc, sparcv9
Red Hat Linux 6.2 – i386, alpha, sparc, sparcv9
3. Problem description:
The dynamic linker ld.so uses several environment variables like
LD_PRELOAD and LD_LIBRARY_PATH to load additional libraries or
modify the library search path. It is unsafe to accept arbitrary
user specified values of these variables when executing setuid
applications, so ld.so handles them specially in setuid programs
and also removes them from the environment.
One of the discovered bugs causes these variables not to be
removed from the environment under certain circumstances. This does
not cause any threat to setuid application themselves, but it could
be exploited if a setuid application does not either drop
privileges or clean up its environment prior to executing other
programs.
A number of additional bugs have been found in glibc locale and
internationalization 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 pathnames for
searching message catalogues or locale files.
Normally, if these variables contain “/” characters, a program
can load the internationalization files from arbitrary directories.
This is unnacceptable for setuid programs, which is why glibc does
not allow certain settings of these variables if the program is
setuid or setgid. However, some of these checks were done in
inappropriate places, contained bugs or were completely missing. It
is highly probable that some of these bugs can be used for local
root exploits.
The Red Hat Linux 6.x updates also fix a linuxthreads deadlock
bug and handling of certain values of the TZ environment
variable.
The previous version of the 6.x errata introduced some threading
problems visible with JDK and Mozilla, the 5.x errata had a bug
which caused several localized programs to die with segmentation
fault at startup.Both of these problems are fixed with this errata
update.
4. Solution:
For each RPM for your particular architecture, run:
rpm -Fvh [filename]
where filename is the name of the RPM.
5. Bug IDs fixed (s(http://bugzilla.redhat.com/bugzilla
for more info):
13785 – Bug in pthreads blocks ability to preempt suspend and
resume threads on SMP machines
17203 – glibc-2.1.3-19 breaks Sun and IBM Java 1.3 on SMP
17187 – tcsh broken after glibc upgrade
6. RPMs required:
Red Hat Linux 5.2:
sparc:
ftp://updates.redhat.com/5.2/sparc/glibc-2.0.7-29.4.sparc.rpm
ftp://updates.redhat.com/5.2/sparc/glibc-debug-2.0.7-29.4.sparc.rpm
ftp://updates.redhat.com/5.2/sparc/glibc-devel-2.0.7-29.4.sparc.rpm
ftp://updates.redhat.com/5.2/sparc/glibc-profile-2.0.7-29.4.sparc.rpm
alpha:
ftp://updates.redhat.com/5.2/alpha/glibc-2.0.7-29.4.alpha.rpm
ftp://updates.redhat.com/5.2/alpha/glibc-debug-2.0.7-29.4.alpha.rpm
ftp://updates.redhat.com/5.2/alpha/glibc-devel-2.0.7-29.4.alpha.rpm
ftp://updates.redhat.com/5.2/alpha/glibc-profile-2.0.7-29.4.alpha.rpm
i386:
ftp://updates.redhat.com/5.2/i386/glibc-2.0.7-29.4.i386.rpm
ftp://updates.redhat.com/5.2/i386/glibc-debug-2.0.7-29.4.i386.rpm
ftp://updates.redhat.com/5.2/i386/glibc-devel-2.0.7-29.4.i386.rpm
ftp://updates.redhat.com/5.2/i386/glibc-profile-2.0.7-29.4.i386.rpm
sources:
ftp://updates.redhat.com/5.2/SRPMS/glibc-2.0.7-29.4.src.rpm
Red Hat Linux 6.2:
sparc:
ftp://updates.redhat.com/6.2/sparc/glibc-2.1.3-21.sparc.rpm
ftp://updates.redhat.com/6.2/sparc/glibc-devel-2.1.3-21.sparc.rpm
ftp://updates.redhat.com/6.2/sparc/glibc-profile-2.1.3-21.sparc.rpm
ftp://updates.redhat.com/6.2/sparc/nscd-2.1.3-21.sparc.rpm
i386:
ftp://updates.redhat.com/6.2/i386/glibc-2.1.3-21.i386.rpm
ftp://updates.redhat.com/6.2/i386/glibc-devel-2.1.3-21.i386.rpm
ftp://updates.redhat.com/6.2/i386/glibc-profile-2.1.3-21.i386.rpm
ftp://updates.redhat.com/6.2/i386/nscd-2.1.3-21.i386.rpm
alpha:
ftp://updates.redhat.com/6.2/alpha/glibc-2.1.3-21.alpha.rpm
ftp://updates.redhat.com/6.2/alpha/glibc-devel-2.1.3-21.alpha.rpm
ftp://updates.redhat.com/6.2/alpha/glibc-profile-2.1.3-21.alpha.rpm
ftp://updates.redhat.com/6.2/alpha/nscd-2.1.3-21.alpha.rpm
sparcv9:
ftp://updates.redhat.com/6.2/sparcv9/glibc-2.1.3-21.sparcv9.rpm
sources:
ftp://updates.redhat.com/6.2/SRPMS/glibc-2.1.3-21.src.rpm
7. Verification:
MD5 sum Package Name
d89ceb98bcbcf4713d16fdee7ff7f43e 5.2/SRPMS/glibc-2.0.7-29.4.src.rpm 6ef2b922267041c5d255929bfc98fd64 5.2/alpha/glibc-2.0.7-29.4.alpha.rpm 888f00bface573ffd88e221c6b6f8e2e 5.2/alpha/glibc-debug-2.0.7-29.4.alpha.rpm ebc93b3ee1f685d50a94dcdb28c61cc9 5.2/alpha/glibc-devel-2.0.7-29.4.alpha.rpm e41785070075562b0481df36478d2fc8 5.2/alpha/glibc-profile-2.0.7-29.4.alpha.rpm 2f2113f874194aa3ecc618c4d1ec35aa 5.2/i386/glibc-2.0.7-29.4.i386.rpm 078735dd7907a1ed391018f8768f08a5 5.2/i386/glibc-debug-2.0.7-29.4.i386.rpm 752e9f9c3ebd3a91eb4ee399cc679186 5.2/i386/glibc-devel-2.0.7-29.4.i386.rpm 1ebdf4fdb6f479e735cf8d9b0190e467 5.2/i386/glibc-profile-2.0.7-29.4.i386.rpm f26d7fada3d250389144b235bf1f3627 5.2/sparc/glibc-2.0.7-29.4.sparc.rpm 92f25cc1809d1c87981184848ebc2c92 5.2/sparc/glibc-debug-2.0.7-29.4.sparc.rpm bde3f83247f4975f50a552bdfe1cfe92 5.2/sparc/glibc-devel-2.0.7-29.4.sparc.rpm 7d466b8c454556801502a5193aa90919 5.2/sparc/glibc-profile-2.0.7-29.4.sparc.rpm 951f8018ee585cbae936f5aabc93975a 6.2/SRPMS/glibc-2.1.3-21.src.rpm 71fc519a3af0c780f04957d0fd30e3ef 6.2/alpha/glibc-2.1.3-21.alpha.rpm 0958d288b68b69172e05c818dadde1df 6.2/alpha/glibc-devel-2.1.3-21.alpha.rpm c3f263f06115287996cf835bda6d831c 6.2/alpha/glibc-profile-2.1.3-21.alpha.rpm 628f153cf8159b150cdf5812ecf8a7f1 6.2/alpha/nscd-2.1.3-21.alpha.rpm 2197ca4a7bce75b8f71e776198ea6ad6 6.2/i386/glibc-2.1.3-21.i386.rpm b8cfd8011077f35ae63f589c494166f2 6.2/i386/glibc-devel-2.1.3-21.i386.rpm bed9b0d02fae36d490d3025de74b5e0f 6.2/i386/glibc-profile-2.1.3-21.i386.rpm 26b9ce91af840a7928ac52a32b5fe2c7 6.2/i386/nscd-2.1.3-21.i386.rpm e2d13625c1869c983a917f6867bc351b 6.2/sparc/glibc-2.1.3-21.sparc.rpm 44d151c0f2e99dd6ed69274c1b2b106e 6.2/sparc/glibc-devel-2.1.3-21.sparc.rpm bef08ed72e52b149da48421369561100 6.2/sparc/glibc-profile-2.1.3-21.sparc.rpm 8f5ee1e544b50f84f71eb2c38e1ef2fe 6.2/sparc/nscd-2.1.3-21.sparc.rpm 7fd0aefa79a7546cb944752c545c651f 6.2/sparcv9/glibc-2.1.3-21.sparcv9.rpm
These packages are GPG signed by Red Hat, Inc. for security. Our
key is available at:
http://www.redhat.com/corp/contact.html
You can verify each package with the following command:
rpm –checksig
If you only wish to verify that each package has not been
corrupted or tampered with, examine only the md5sum with the
following command:
rpm –checksig –nogpg
8. References:
http://www.securityfocus.com/templates/archive.pike?threads=0&start=2000-08-27&mid=79537&fromthread=1&list=1&end=2000-09-02&
Copyright(c) 2000 Red Hat, Inc.