Apache Advisory: kernel, xinetd have Dos and Root compromise found

posted onOctober 20, 2001

by hitbsecnews

Engarde Secure Linux has released three security updates: one to its Apache package, one to xinetd, and one to address the local DoS and root compromise recently identified in the Linux kernel.

Date: Fri, 19 Oct 2001 12:16:02 -0400 (EDT)
From: EnGarde Secure Linux
Subject: [ESA-20011019-01] Two apache vulnerabilities

+------------------------------------------------------------------------+
| EnGarde Secure Linux Security Advisory October 19, 2001 |
| http://www.engardelinux.org/ ESA-20011019-01 |
| |
| Package: apache |
| Summary: Two apache vulnerabilities |
+------------------------------------------------------------------------+

EnGarde Secure Linux is a secure distribution of Linux that features
improved access control, host and network intrusion detection, Web
based secure remote management, complete e-commerce using AllCommerce,
and integrated open source security tools.

OVERVIEW
- --------
There are two vulnerabilities in apache which can allow an
attacker to write to arbitrary files or view directory indexes when
they are not supposed to, in some configurations.

DETAIL
- ------
The following items are from the "Announcement" file included in the
Apache 1.3.22 tarball:

* A vulnerability was found in the split-logfile support program. A
request with a specially crafted Host: header could allow any file
with a .log extension on the system to be written to. PR#7848
CAN-2001-0730

* A vulnerability was found when Multiviews are used to negotiate
the directory index. In some configurations, requesting a URI with
a QUERY_STRING of M=D could return a directory listing rather than
the expected index page. CAN-2001-0731

The Common Vulnerabilities and Exposures project (cve.mitre.org/) has
assigned the names CAN-2001-0730 and CAN-2001-0731 to these issues.

SOLUTION
- --------
All users should upgrade to the most recent version, as outlined in
this advisory.

Guardian Digital recently made available the Guardian Digital Secure
Update, a means to proactively keep systems secure and manage
system software. EnGarde users can automatically update their system
using the Guardian Digital WebTool secure interface.

If choosing to manually upgrade this package, updates can be
obtained from:

ftp://ftp.engardelinux.org/pub/engarde/stable/updates/
http://ftp.engardelinux.org/pub/engarde/stable/updates/

Before upgrading the package, the machine must either:

a) be booted into a "standard" kernel; or
b) have LIDS disabled.

To disable LIDS, execute the command:

# /sbin/lidsadm -S -- -LIDS_GLOBAL

To install the updated package, execute the command:

# rpm -Uvh

To re-enable LIDS (if it was disabled), execute the command:

# /sbin/lidsadm -S -- +LIDS_GLOBAL

To verify the signature of the updated packages, execute the command:

# rpm -Kv

UPDATED PACKAGES
- ----------------
These updated packages are for EnGarde Secure Linux 1.0.1 (Finestra).

Source Packages:

SRPMS/apache-1.3.22-1.0.26.src.rpm
MD5 Sum: 181b1b14d60b3e9268fdc979ac0b3c98

Binary Packages:

i386/apache-1.3.22-1.0.26.i386.rpm
MD5 Sum: 96572199eee00807d35b8c78d1fcc011

i686/apache-1.3.22-1.0.26.i686.rpm
MD5 Sum: 17a01bce42ad8d34ec4e87ef2949fc90

REFERENCES
- ----------

Guardian Digital's public key:
http://ftp.engardelinux.org/pub/engarde/ENGARDE-GPG-KEY

Apache's Official Web Site:
http://httpd.apache.org/

Security Contact: security@guardiandigital.com
EnGarde Advisories: http://www.engardelinux.org/advisories.html

- --------------------------------------------------------------------------
$Id: ESA-20011019-01-apache,v 1.1 2001/10/18 20:09:53 rwm Exp $
- --------------------------------------------------------------------------
Author: Ryan W. Maple,
Copyright 2001, Guardian Digital, Inc.

Date: Fri, 19 Oct 2001 12:16:32 -0400 (EDT)
From: EnGarde Secure Linux
Subject: [ESA-20011019-02] kernel: Local DoS and root compromise

+------------------------------------------------------------------------+
| EnGarde Secure Linux Security Advisory October 19, 2001 |
| http://www.engardelinux.org/ ESA-20011019-02 |
| |
| Package: kernel |
| Summary: Local DoS and root compromise |
+------------------------------------------------------------------------+

OVERVIEW
- --------
There are two vulnerabilities in the kernel which can allow a local
attacker to either obtain root privileges or lock the machine up for
an arbitrary amount of time.

DETAIL
- ------
There are two vulnerabilities in the version of the kernel which
shipped with EnGarde v1.0.1:

1) There is another local root exploit using the kernel's ptrace
capabilities.

2) The kernel can be forced to remain in path_walk() while
traversing a very deep tree of symbolic links for an arbitrary
amount of time, resulting in a local DoS attack.

Both vulnerabilities were discovered by Nergal (nergal@7bulls.com).

A note from Nergal's advisory:

"In order for this flaw to be exploitable, /usr/bin/newgrp must be
setuid root and world-executable. Additionally, newgrp, when run
with no arguments, should not prompt for password. This conditions
are satisfied in case of most popular Linux distributions (but not
Openwall GNU/*/Linux)."

Please note that EnGarde Secure Linux does not ship with the 'newgrp'
utility, nor does it ship with any other setuid/setgid executables
which can be used to exploit this bug. Thus, EnGarde Secure Linux is
not vulnerable to the ptrace flaw (item #1 above).

Both vulnerabilies are very serious and all users are recommended to
upgrade immediately using the special SOLUTION in this advisory.

SOLUTION
- --------
All users should upgrade to the most recent version, as outlined in
this advisory.

Please note that kernel upgrades are not available through Guardian
Digital Secure Update. Please follow the steps outlined below to
upgrade your system manually. Updates can be obtained from:

ftp://ftp.engardelinux.org/pub/engarde/stable/updates/
http://ftp.engardelinux.org/pub/engarde/stable/updates/

Please read and understand this entire section before you attempt to
upgrade the kernel.

Initial Steps
-------------
1) Verify the machine is either:

a) booted into a "standard" kernel; or
b) LIDS is disabled (/sbin/lidsadm -S -- -LIDS_GLOBAL)

2) Determine which kernels you currently have installed:

# rpm -qa --qf "%{NAME}
" | grep kernel

3) Download the new kernels that match what you have installed
(based on step 2) from the "UPDATED PACKAGES" section of this
advisory.

Installation Steps
------------------
4) Install the new packages. The packages will automagically
update /etc/lilo.conf by commenting out any old EnGarde images
and replacing them with the new ones:

# rpm -i ...

5) Re-run LILO. If you see any errors then open /etc/lilo.conf in
your favorite text editor and make the appropriate changes:

# /sbin/lilo

Final Steps
-----------
6) If you did not see any LILO errors then your new kernel is now
installed and your machine is ready to be rebooted:

# reboot

UPDATED PACKAGES
- ----------------
These updated packages are for EnGarde Secure Linux 1.0.1 (Finestra).

Source Packages:

SRPMS/kernel-2.2.19-1.0.20.src.rpm
MD5 Sum: 6a58f06ed68b1d7d967f523712ee8835

Binary Packages:

i386/kernel-2.2.19-1.0.20.i386.rpm
MD5 Sum: 3704b6ced3c76c02c52238768cdeb1f3

i386/kernel-lids-mods-2.2.19-1.0.20.i386.rpm
MD5 Sum: f4140c01e414e52204a4bab8ac600fa7

i386/kernel-smp-lids-mods-2.2.19-1.0.20.i386.rpm
MD5 Sum: d02eb3e039cc37f15c7e6e56ece2d35a

i386/kernel-smp-mods-2.2.19-1.0.20.i386.rpm
MD5 Sum: dd89db42a52786e3aeaf17deab647df4

i686/kernel-2.2.19-1.0.20.i686.rpm
MD5 Sum: 0854c91dd5d178e44655d836da5d2fd3

i686/kernel-lids-mods-2.2.19-1.0.20.i686.rpm
MD5 Sum: 98823cfce2f4e4d8c7f10372e7fc6971

i686/kernel-smp-lids-mods-2.2.19-1.0.20.i686.rpm
MD5 Sum: 502b174927b2361eebd58e93422cbb25

i686/kernel-smp-mods-2.2.19-1.0.20.i686.rpm
MD5 Sum: e38e6b160c5d91fb64b02744b845b0b2

REFERENCES
- ----------

Guardian Digital's public key:
http://ftp.engardelinux.org/pub/engarde/ENGARDE-GPG-KEY

Credit for the discovery of this bug goes to:
Rafal Wojtczuk

Official Web Site of the Linux Kernel:
http://www.kernel.org/

Security Contact: security@guardiandigital.com
EnGarde Advisories: http://www.engardelinux.org/advisories.html

- --------------------------------------------------------------------------
$Id: ESA-20011019-02-kernel,v 1.3 2001/10/18 20:26:35 rwm Exp $
- --------------------------------------------------------------------------
Author: Ryan W. Maple,
Copyright 2001, Guardian Digital, Inc.

Date: Fri, 19 Oct 2001 12:17:05 -0400 (EDT)
From: EnGarde Secure Linux
Subject: [ESA-20011019-03] xinetd: Several potential vulnerabilities

+------------------------------------------------------------------------+
| EnGarde Secure Linux Security Advisory October 19, 2001 |
| http://www.engardelinux.org/ ESA-20011019-03 |
| |
| Package: xinetd |
| Summary: Several potential vulnerabilities |
+------------------------------------------------------------------------+

OVERVIEW
- --------
There are some potential vulnerabilities in the most recent xinetd
package for EnGarde Secure Linux 1.0.1.

DETAIL
- ------
Solar Designer did an audit of xinetd 2.3.0 and came up with a list
of potential vulnerabilities. This release fixes all known
vulnerabilities as a precautionary measure. Most of these fixes are
in the interest of robustness and are not known to be exploitable at
this time.

For more information on the results of this audit please refer to
the AUDIT file in the xinetd-2.3.3.tar.gz/ tarball (included with
the source package).

SOLUTION
- --------
All users should upgrade to the most recent version, as outlined in
this advisory.

If choosing to manually upgrade this package, updates can be
obtained from:

ftp://ftp.engardelinux.org/pub/engarde/stable/updates/
http://ftp.engardelinux.org/pub/engarde/stable/updates/

Before upgrading the package, the machine must either:

a) be booted into a "standard" kernel; or
b) have LIDS disabled.

To disable LIDS, execute the command:

# /sbin/lidsadm -S -- -LIDS_GLOBAL

To install the updated package, execute the command:

# rpm -Uvh

To re-enable LIDS (if it was disabled), execute the command:

# /sbin/lidsadm -S -- +LIDS_GLOBAL

To verify the signature of the updated packages, execute the command:

# rpm -Kv

UPDATED PACKAGES
- ----------------
These updated packages are for EnGarde Secure Linux 1.0.1 (Finestra).

Source Packages:

SRPMS/xinetd-2.3.3-1.0.19.src.rpm
MD5 Sum: e67cb1e11599c9a9ce0b58ef9fe04472

Binary Packages:

i386/xinetd-2.3.3-1.0.19.i386.rpm
MD5 Sum: 41c24df4e59ae3e3e6a6fe5db4d1f64d

i686/xinetd-2.3.3-1.0.19.i686.rpm
MD5 Sum: 76df066a15dbc80456203bb4e945eaa0

REFERENCES
- ----------
Guardian Digital's public key:
http://ftp.engardelinux.org/pub/engarde/ENGARDE-GPG-KEY

xinetd's Official Web Site:
http://www.xinetd.org/

Security Contact: security@guardiandigital.com
EnGarde Advisories: http://www.engardelinux.org/advisories.html

- --------------------------------------------------------------------------
$Id: ESA-20011019-03-xinetd,v 1.1 2001/10/18 20:10:18 rwm Exp $
- --------------------------------------------------------------------------
Author: Ryan W. Maple,
Copyright 2001, Guardian Digital, Inc.