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Linux TCP Flaw Fix

18/08/2016

For those who want to know all the details here is a document which explains how this RFC 5961 flaw can be exploited:

http://www.cs.ucr.edu/~zhiyunq/pub/sec16_TCP_pure_offpath.pdf

The fix itself:

net.ipv4.tcp_challenge_ack_limit = 999999999

which is appended to

/etc/sysctl.conf file using a text editor

and applied with

sysctl -p

Most importantly a command to show if your Linux OS is patched already – I had to trawl quite a bit to find this https://community.centminmod.com/threads/linux-tcp-flaw-cve-2016-5696-allows-hackers-to-hijack-net-traffic-inject-malware-remotely.8304/

sysctl -a | grep ack_limit
net.ipv4.tcp_challenge_ack_limit = 100

As you can see from above it was set to 100 on my desktop running Ubuntu 14.04 with all the updates on 18/08/16.

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Windows 10 No Start Menu

14/07/2016

No Start Menu when you click Start button and right-click not working on Taskbar program launch icons.

Try clicking on on Notifications icon (bottom RH corner) and toggle off Tablet Mode

Windows SP1 Convenience Rollup

02/07/2016

The Windows SP1 Convenience Rollup (WSCR) updates a clean copy of Windows SP1 from  Feb 2011 to May 2016. Further updates are then installed as normal

Steps

  1. Install a clean copy of Windows 7 SP1
  2. Install April 2015 Servicing Stack Update from https://support.microsoft.com/en-us/kb/3020369 and click the appropriate “Download the package now” link
  3. Go to http://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB3125574  and click the Install button at the bottom of the page; click Yes and click the Add button for your version of Windows from the 3 choices shown.

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Rename Windows Home Folder

18/06/2016

The examples given change the user’s home folder from Michael to John.

In case of mistakes and recover data you may have missed make an image backup. Additionally create a restore point to backup the registry.

Method 1 – create new user and delete the old one

The recommended approach. It’s a bit sledge-hammer but is reliable and has the benefit of cleaning up the user profile.

  1. Create a new account called John using Control Panel or Windows 10 PC Settings >

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Firefox about:config Locale Settings

24/05/2016

In Firefox URL box enter about:config to view | edit your default locale search and language settings:

  • general.useragent.locale
  • browser.search.countryCode
  • browser.search.region
  • browser.search.isUS

UK values for above  = en.GB, GB, GB, False

Create ISO file from CD/DVD using DD

15/05/2016

In Linux/Ubuntu to create an ISO from a CD/DVD is simplicity itself using the DD command

Use lsbk to determine the CD device name

lsblk
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0   1.8T  0 disk
├─sda1   8:1    0    50G  0 part /
├─sda2   8:2    0    10G  0 part [SWAP]
├─sda3   8:3    0   1.6T  0 part /home
└─sda4   8:4    0    50G  0 part
sdb      8:16   0   1.8T  0 disk
├─sdb1   8:17   0   100G  0 part
├─sdb2   8:18   0    20G  0 part
├─sdb3   8:19   0   250G  0 part
├─sdb4   8:20   0     1K  0 part
├─sdb5   8:21   0    50G  0 part
├─sdb6   8:22   0  1000G  0 part /media/NTFS_DATA
└─sdb7   8:23   0   443G  0 part
sr0     11:0    1  25.6M  0 rom  /media/mike/NEW 
loop1    7:1    0  25.6M  1 loop /media/iso

Create ISO file with DD

dd if=/dev/sr0 of=/home/mike/Downloads/test.iso

Create Mount Point

sudo mkdir /media/iso

Mount ISO file

sudo mount -o loop /home/mike/Downloads/test.iso /media/iso

Unmount ISO File

sudo umount /media/iso

Remove Mount Point

sudo rmdir /media/iso

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How to remove Home screen Google Search widget

15/04/2016

Here’s to remove the Google Search widget from your Lollipop v5.1.1 Home screen.

  1. Press and hold on any free space on the Home screen to bring up the desktop customiser
  2. Tap the Settings cog in the bottom right corner to bring up Preferences
  3. Within “Home Screen Settings” turn off “Show search bar”

Resources

Change Yosemite Mail Default Message Font Colour

07/04/2016

This is a work around for setting the Message default font colour.

Create a signature with Mail -> Preferences -> Signature selecting the mail account and + button like the one below in blue or desired colour:

 Hello

Regards,

Joe Bloggs

Now when you send a new message this signature will appear. If you insert your message between Hello and Regards it will be blue.