≡ Menu

Security Alert

Web server that use threaded processes such as Apache and others can be targeted using interesting HTTP DoS tool that has been released in wild. Tool can eat up all resources while it holds the connection open to server and keep sending incomplete HTTP requests. End result Apache run out of memory and comes under DoS attack.
[click to continue…]

Linux / BSD and UNIX like operating systems includes software from the OpenSSL Project. The OpenSSL is commercial-grade, industry-strength, full-featured Open Source toolkit implementing the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) protocols as well as general purpose cryptography library.

The Google security team discovered a flaw in the way OpenSSL checked the verification of certificates. An attacker in control of a malicious server, or able to effect a "man in the middle" attack, could present a malformed SSL/TLS signature from a certificate chain to a vulnerable client and bypass validation.

This update has been rated as having important security impact on FreeBSD, all version of Ubuntu / Debian, Red Hat (RHEL), CentOS, Fedora and other open source operating system that depends upon OpenSSL.
[click to continue…]

Debian GNU/Linux 4.0 Update 6 Released

Didn't take long to release new updated version.

The Debian project is pleased to announce the sixth update of its stable distribution Debian GNU/Linux 4.0 (codename "etch"). This update mainly adds corrections for security problems to the stable release, along with a few adjustment to serious problems. This update has been rated as having important security impact. You are advised to upgrade system ASAP.
[click to continue…]

Mozilla Patches 8 Security Flaws

Mozilla has released software updates to fix at least 8 security vulnerabilities (3 critical bugs) in its Firefox software for the Windows, Linux, Mac and other platforms. You can now download Firefox version 3.0.5. This update has been rated as having important security impact.
[click to continue…]

Debian project today released a pair of security updates to plug at least ten security holes in its core called Linux kernel. Several vulnerabilities have been discovered in the Linux kernel that may lead to a denial of service or privilege escalation. This update has been rated as having important security impact.
[click to continue…]

Debian PHP 5 Security Issues

Debian 5 php5 package has serious security issues as follows:

To prevent Denial of Service attacks by exhausting the number of available temporary file names, the max_file_uploads option introduced in PHP 5.3.1 has been backported.
[click to continue…]

FreeBSD today released a core (kernel) patched to plug "arc4random predictable sequence vulnerability" security hole in its operating systems version 6.x and 7.x stable release. When the arc4random random number generator is initialized, there may be inadequate entropy to meet the needs of kernel systems which rely on arc4random; and it may take up to 5 minutes before arc4random is reseeded with secure entropy from the Yarrow random number generator. All security-related kernel subsystems that rely on a quality random number generator are subject to a wide range of possible attacks. This update has been rated as having important security impact.

More about arc4random

arc4random(9) is a generic-purpose random number generator based on the key stream generator of the RC4 cipher. It is expected to be cryptographically strong, and used throughout the FreeBSD kernel for a variety of purposes, some of which rely on its cryptographic strength. arc4random(9) is periodically reseeded with entropy from the FreeBSD kernel's Yarrow random number generator, which gathers entropy from a variety of sources including hardware interrupts. During the boot process, additional entropy is provided to the Yarrow random number generator from userland, helping to ensure that adequate entropy is present for cryptographic purposes.

Impact

All security-related kernel subsystems that rely on a quality random number generator are subject to a wide range of possible attacks for the 300 seconds after boot or until 64k of random data is consumed.

How do I patch my FreeBSD system?

Upgrade your vulnerable system to 6-STABLE, or 7-STABLE, or to the RELENG_7_0, or RELENG_6_3 security branch using csup command. This will fix the problem.

How to patch current system?

The following patches have been verified to apply to FreeBSD 6.3 and 7.0 systems.

Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility.

Download FreeBSD 7.x patch

# cd /tmp
# fetch http://security.FreeBSD.org/patches/SA-08:11/arc4random.patch
# fetch http://security.FreeBSD.org/patches/SA-08:11/arc4random.patch.asc

Verify patch, enter:
# gpg --verify arc4random.patch.asc arc4random.patch

To apply the patch, enter:
# cd /usr/src
# patch /tmp/arc4random.patch

Download FreeBSD 6.x patch

# cd /tmp
# fetch http://security.FreeBSD.org/patches/SA-08:11/arc4random6x.patch
# fetch http://security.FreeBSD.org/patches/SA-08:11/arc4random6x.patch.asc

Verify patch, enter:
# gpg --verify arc4random6x.patch.asc arc4random6x.patch
To apply the patch, enter:
# cd /usr/src
# patch /tmp/arc4random6x.patch

Recompile your kernel

Now recompile your kernel:
# make kernel KERNCONF=GENERIC
# make installkernel KERNCONF=GENERIC

Replace GENERIC with your actual kernel name. Finally, reboot the system:
# reboot
Make sure everything is working fine, enter:
# uname -a
# tail -f /var/log/messages
# tail -f /path/to/other/log/files
# sockstat

Please see FreeBSD handbook for more information.