Java Zero Day Flaw Under Attack

Taken from  Experts Suggest Disabling Java after Zero-Day Flaw Discovery

Security firm FireEye released information yesterday on a Java flaw that has been seen in targeted attacks in the wild, and has been tested to work on most major Web browsers for both Mac and PC.

According to researchers, all versions of Java (including the Java 7 Update 6) are susceptible to attack, and can lead to the installation of malware on a system.

The hole is due to an issue in how the "setSecurityManager()" function in Java is called. Attackers can exploit this issue and set its own privileges on a targeted system, allowing the downloading and execution of malicious software. 

Read on for more information.........

Proposed workaround:

1. Read US-CERT Vulnerability Note VU#636312

Other Information:

1.  Warning: Java Zero Day Flaw Under Attack

Persistent VNC Session for users for CentOS

If you are intending to setup a persistent VNC Session for selected users, you can edit the global settings at /etc/sysconfig/vncservers.

# vim /etc/sysconfig/vncservers 

# The VNCSERVERS variable is a list of display:user pairs.
#
# Uncomment the lines below to start a VNC server on display :2
# as my 'myusername' (adjust this to your own).  You will also
# need to set a VNC password; run 'man vncpasswd' to see how
# to do that.
#
# DO NOT RUN THIS SERVICE if your local area network is
# untrusted!  For a secure way of using VNC, see this URL:
# http://kbase.redhat.com/faq/docs/DOC-7028

# Use "-nolisten tcp" to prevent X connections to your VNC server via TCP.

# Use "-localhost" to prevent remote VNC clients connecting except when
# doing so through a secure tunnel.  See the "-via" option in the
# `man vncviewer' manual page.

# VNCSERVERS="2:myusername"
# VNCSERVERARGS[2]="-geometry 800x600 -nolisten tcp -localhost"

VNCSERVERS="2:user1"
VNCSERVERS="3:user2"
VNCSERVERARGS[2]="-geometry 1280x800 -depth 16"
VNCSERVERARGS[3]="-geometry 1024x768"

Once done, you just restart the vncserver services

# service vncserver restart

Changing the screen size of vnc client using command line

If you are using vnc client like Real VNC, you can easily change the size of the vnc screen by clicking scale to window size, something like the screen shot below.

But if you wish to use the command line to determine the size, you can set the screen by specifying

# vncserver -geometry 1280x800

You can verify the size by using the command by using the command

# xdpinfo -display :display_number

  dimensions:    1280x800 pixels (325x203 millimeters)
  resolution:    100x100 dots per inch
  depths (7):    1, 4, 8, 16, 24, 32, 16

  root window id:    0x3a
  depth of root window:    16 planes
  number of colormaps:    minimum 1, maximum 1
  default colormap:    0x20
  default number of colormap cells:    64
  preallocated pixels:    black 0, white 65535
  options:    backing-store YES, save-unders YES
  largest cursor:    1280x800...
   ...
   ...
   ...

Installing and compiling LimitCPU

LimitCPU is a program to throttle the CPU cycles used by other applications. LimitCPU will monitor a process and make sure its CPU usage stays at or below a given percentage......

Compiling and Installing is not difficult. Do look at the README

# cd cpulimit-1.7
# make
# make install

To remove the installation, do

# make deinstall

Common Usage
With Reference to LimitCPU README

1. For  example, if you wish to cap the cpu usage to 50% for processor 12345

# cpulimit -p 12345 -l 50

2. If you wish to run LimitCPU in the background

# cpulimit -p 12345 -l 50 -b

3. If you wish to limit running processes based on their name instead of their process ID. The below example will keep an eye on "bigexe" and, if the application quits and another program called "bigexe" is run, LimitCPU will monitor the new process too. Pretty cool eh

# cpulimit --exe /usr/bin/bigexe --limit 50

4. If you wish to only track the first program and then exit

# cpulimit --exec /usr/bin/bigexe --limit 50 -z

Installing GPFS 3.4 Packages on a Linux Client

In this work-in-progress tutorial, I will write how to install the General Parallel File System (GPFS) packages and compile portability layer (gpfs.gplbin) for each kernel or  architecture. For more information, see Installing GPFS 3.4 Packages on a Client

Do read Adding nodes to a GPFS cluster