Red Hat: 2012:0152-03: kexec-tools: Moderate Advisory
Posted by Benjamin D. Thomas   
RedHat Linux An updated kexec-tools package that resolves three security issues, fixes several bugs and adds various enhancements is now available for Red Hat Enterprise Linux 5. [More...]
                   Red Hat Security Advisory

Synopsis:          Moderate: kexec-tools security, bug fix, and enhancement update
Advisory ID:       RHSA-2012:0152-03
Product:           Red Hat Enterprise Linux
Advisory URL:
Issue date:        2012-02-21
CVE Names:         CVE-2011-3588 CVE-2011-3589 CVE-2011-3590 

1. Summary:

An updated kexec-tools package that resolves three security issues, 
fixes several bugs and adds various enhancements is now available for 
Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having moderate
security impact. Common Vulnerability Scoring System (CVSS) base scores,
which give detailed severity ratings, are available for each vulnerability
from the CVE links in the References section.

2. Relevant releases/architectures:

Red Hat Enterprise Linux (v. 5 server) - i386, ia64, ppc, s390x, x86_64
Red Hat Enterprise Linux Desktop (v. 5 client) - i386, x86_64

3. Description:

The kexec-tools package contains the /sbin/kexec binary and utilities that 
together form the user-space component of the kernel's kexec feature. The 
/sbin/kexec binary facilitates a new kernel to boot using the kernel's 
kexec feature either on a normal or a panic reboot. The kexec fastboot 
mechanism allows booting a Linux kernel from the context of an already 
running kernel.

Kdump used the SSH (Secure Shell) "StrictHostKeyChecking=no" option when
dumping to SSH targets, causing the target kdump server's SSH host key not
to be checked. This could make it easier for a man-in-the-middle attacker
on the local network to impersonate the kdump SSH target server and
possibly gain access to sensitive information in the vmcore dumps.

The mkdumprd utility created initrd files with world-readable permissions.
A local user could possibly use this flaw to gain access to sensitive 
information, such as the private SSH key used to authenticate to a remote 
server when kdump was configured to dump to an SSH target. (CVE-2011-3589)

The mkdumprd utility included unneeded sensitive files (such as all files 
from the "/root/.ssh/" directory and the host's private SSH keys) in the 
resulting initrd. This could lead to an information leak when initrd 
files were previously created with world-readable permissions. Note: With 
this update, only the SSH client configuration, known hosts files, and the 
SSH key configured via the newly introduced sshkey option in 
"/etc/kdump.conf" are included in the initrd. The default is the key 
generated when running the "service kdump propagate" command, 
"/root/.ssh/kdump_id_rsa". (CVE-2011-3590)

Red Hat would like to thank Kevan Carstensen for reporting these issues.

This updated kexec-tools package also includes numerous bug fixes and
enhancements. Space precludes documenting all of these changes in this
advisory. Users are directed to the Red Hat Enterprise Linux 5.8 Technical
Notes, linked to in the References, for information on the most significant
of these changes.

All users of kexec-tools are advised to upgrade to this updated package, 
which resolves these security issues, fixes these bugs and adds these 

4. Solution:

Before applying this update, make sure all previously-released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at

5. Bugs fixed (

662530 - ln: creating symbolic link `/tmp/initrd.ta4308/lib/' to `/lib/power6/': File exists
678308 - kexec kernel crashes due to use of reserved memory range
709622 - Non-portable "while" loop form used
716439 - CVE-2011-3588 CVE-2011-3589 CVE-2011-3590 kexec-tools: Multiple security flaws by management of kdump core files and ramdisk images
748319 - fsck: WARNING: couldn't open /etc/fstab: No such file or directory

6. Package List:

Red Hat Enterprise Linux Desktop (v. 5 client):




Red Hat Enterprise Linux (v. 5 server):







These packages are GPG signed by Red Hat for security.  Our key and 
details on how to verify the signature are available from

7. References:

8. Contact:

The Red Hat security contact is .  More contact
details at

Copyright 2012 Red Hat, Inc.