Red Hat Linux General Security Advisory

 
Red Hat, Inc. Security Advisory
Synopsis ypbind for Red Hat Linux 5.x, 6.x has a local root exploit

Advisory ID RHSA-2000:086-05

Issue Date 2000-10-16

Updated On 2000-10-23

Product Red Hat Linux

Keywords ypbind string format buffer overflow syslog

Cross References N/A



1. Topic:

ypbind as shipped in Red Hat Linux 5.x and 6.x is vulnerable to a local
root exploit. All systems making use of NIS services are encouraged to
upgrade.

2. Problem description:

Systems using Network Information Service, or NIS, use a daemon called
ypbind to request information from a NIS server. This information is then
used by the local machine. The logging code in ypbind is vulnerable to a
printf string format attack which an attacker could exploit by passing
ypbind a carefully crafted request. This attack can successfully lead to
local root access.

This problem has been corrected with these new packages.

3. Bug IDs fixed: (see bugzilla for more information)

N/A -

4. Relevant releases/architectures:

Red Hat Linux 5.0 - i386, alpha, sparc
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
Red Hat Linux 6.2 - i386, alpha, sparc
Red Hat Linux 6.2EE - i386, alpha, sparc

5. RPMs required:

Red Hat Linux 5.x:

alpha:
ftp://updates.redhat.com/5.2/en/os/alpha/ypbind-3.3-10.alpha.rpm

sparc:
ftp://updates.redhat.com/5.2/en/os/sparc/ypbind-3.3-10.sparc.rpm

i386:
ftp://updates.redhat.com/5.2/en/os/i386/ypbind-3.3-10.i386.rpm

sources:
ftp://updates.redhat.com/5.2/en/os/SRPMS/ypbind-3.3-10.src.rpm

Red Hat Linux 6.x:

alpha:
ftp://updates.redhat.com/6.2/en/os/alpha/ypbind-1.7-0.6.x.alpha.rpm

sparc:
ftp://updates.redhat.com/6.2/en/os/sparc/ypbind-1.7-0.6.x.sparc.rpm

i386:
ftp://updates.redhat.com/6.2/en/os/i386/ypbind-1.7-0.6.x.i386.rpm

sources:
ftp://updates.redhat.com/6.2/en/os/SRPMS/ypbind-1.7-0.6.x.src.rpm

6. Solution:

If you do not use NIS, you should remove ypbind:

rpm -e ypbind

Otherwise, for each RPM for your particular architecture, run:

rpm -Fvh [filename]

where filename is the name of the RPM.

You should then make sure that the new ypbind is running by issuing:

/etc/rc.d/init.d/ypbind restart

7. Verification:

MD5 sum                           Package Name
-------------------------------------------------------------------------
507ff0e63468e829b2c917789ba2fedd  5.2/en/os/SRPMS/ypbind-3.3-10.src.rpm
127274f9828d27f895e8d8eee8d38db6  5.2/en/os/alpha/ypbind-3.3-10.alpha.rpm
7bbf68a42a3c996c6f69b5ffaf2911f7  5.2/en/os/i386/ypbind-3.3-10.i386.rpm
3d0cd8b8700182b9b815525e1f99c82d  5.2/en/os/sparc/ypbind-3.3-10.sparc.rpm
d8caa439a1b6c7b26f843bacd01c65f8  6.2/en/os/SRPMS/ypbind-1.7-0.6.x.src.rpm
3a426e3060d31aa37b2a41d973ac3f63  6.2/en/os/alpha/ypbind-1.7-0.6.x.alpha.rpm
411017238af9a0a8891bd3078547336c  6.2/en/os/i386/ypbind-1.7-0.6.x.i386.rpm
3beff51d6a0292fd9d50fe24d07097ac  6.2/en/os/sparc/ypbind-1.7-0.6.x.sparc.rpm

These packages are GPG signed by Red Hat, Inc. for security. Our key is available at:
http://www.redhat.com/about/contact.html

You can verify each package with the following command: rpm --checksig filename

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 filename

Note that you need RPM >= 3.0 to check GnuPG keys.

8. References:

N/A