Symbol not found: __PyCodeInfo_GetIncrementalDecoder

After upgrading the version of Python on my Mac, I immediately got the above error when attempting to run a Python script. You can quickly test by typing

python
import io

and you’ll get the error

Quick digging around on Google revealed what was happening. When a new version of Python is installed, you may need to tell bash to reset the ‘cached’ location to Python. There’s two ways of achieving that

1) Log out and then log back in
or
2) At the terminal prompt, type

hash -r python
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El Capitan download & Squid proxy

Last night I left my Mac downloading the update to El Capitan overnight so it would be ready for me to install following the morning.

I was greeted by a rather generic message saying that the download had failed. A bit of digging showed 2.15Gb had been downloaded before the failure. Maybe it was network disruption; I live in the countryside and it’s not unknown for the VDSL to drop out. Nothing to worry about, downloads resume from where they left off , so I tried again.

It failed again.

And again.

Activated debug mode for AppStore , cleared cookies, reset application and set the Debug level to 2.

Waited

And it failed again at the same point.

Browse of the App Store log file showed NSURLErrorDomain – 1005

Which was helpful in the same way that bricks are to aerodynamics.

Between the internet and my home network is a Squid proxy. I decided to eliminate that as a possible cause.

Several mouse clicks later and El Capitan is downloading without any errors.

Right now I don’t have time to investigate why Squid caused a failure ( max size of cache objects? ) but if others are in a similar situation , switch off the web proxy on your Mac.

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Zero stop day is fast approaching

Busy day today securely wiping and then installing operating systems onto 1 x MacBook Air, 2 x Dell Workstations and a Lenovo W500.

All going back to Novell / MicroFocus tomorrow.

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Time for a change

After almost 8 years, I am moving on from Novell. I handed in my resignation last Friday 24th April and will be leaving towards the end of May.

Whilst at Novell I have met and worked with great people on some fantastic products. I wish them all the best in the future.

For me, I’m onto new adventures with a U.K based security company — Sophos.

Jon

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Thou shalt not install infidel software on the holy domain controller

Unless you really really have to.

In my case I needed to install VMware vsphere 5.5 client onto my lab domain controller. VMware had other ideas and clearly had decided that they needed to save my soul and prevented me from doing so.

Happily, you can override Bishop VMware by using a tool of the devil – a command line switch /VSKIP_OS_CHECKS=”1″ with the VMware client installer. Here’s an example

VMware-viclient-all-5.5.0-1281650.exe /VSKIP_OS_CHECKS="1"

Apostates rejoice !

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Rename Active Domain Controller

Permissions

You must be a member of the Domain Admins group.

WARNING

Reboot will be required

Process

To rename a DC with the name from MY-SERVER in the PMLAB.LOCAL domain to DC-SERVER follow the next steps:

1. Open Command Prompt and type:

NETDOM computername MY-SERVER.PMLAB.LOCAL /add:DC-SERVER.PMLAB.LOCAL

This command will update the service principal name (SPN) attributes in Active Directory for this computer account, and register DNS resource records for the new computer name. The SPN value of the computer account must be replicated to all DCs for the domain, and the DNS resource records for the new computer name must be distributed to all the authoritative DNS servers for the domain name. If the updates and registrations have not occurred prior to removing the old computer name, then some clients may be unable to locate this computer using the new or old name. Therefore, it’s very important to wait till the Active Directory replication finishes a replication cycle. You can check that by using tools such as REPADMIN and REPLMON.

You can verify the new name was indeed added to the computer object by viewing it through ADSIEDIT.MSC (which, for Windows Server 2008, is installed by default). Navigate to the computer object and right-click it. Select Properties:

Scroll down in the list of available attributes till you reach the attribute called msDS-AdditionalDnsHostName.

2. Ensure the computer account updates and DNS registrations are completed, then type:

NETDOM computername MY-SERVER.PMLAB.LOCAL /makeprimary:DC-SERVER.PMLAB.LOCAL

Again, you can inspect the change with ADSIEDIT.MSC. Scroll down in the list of available attributes for the computer object (notice how the server now appears with the new name) till you reach the attribute called msDS-AdditionalDnsHostName.

Notice that the old name should appear in the attribute’s properties.

3. Restart the computer.

4. From the command prompt, type:

NETDOM computername DC-SERVER.PETRI.LOCAL /remove:MY-SERVER.PMLAB.LOCAL

5. Make sure that the changes have successfully been replicated to all the DCs.

 

Adapted from Perti IT Knowledge base
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Cats, coffee and Elephants

As part of my job at Novell I get to travel around various places.  This has given me the chance to try numerous types of coffee across many countries and cultures. Coffee itself has an interesting history, starting with the legend of Kaldi. Kaldi was a goat herder who noticed his goats became somewhat animated after eating berries from a certain bush. History is quiet on if parents had told him not to eat berries from a bush; clearly they had not mentioned anything about picking the berries, throwing them into a fire and then using the roast beans to create the drink we know today as coffee.

Coffee was cultivated, traded and drank throughout the Middle East before spreading worldwide. The first coffee houses, known as qahveh khaneh, also began to appear at this time. Entertainment, musical performances, chess and news of day were all available to those imbibing of the black stuff.

Your local coffee shop may offer some or all of those things; they may even be on the menu although it’s unlikely you’d be able to buy Black Ivory Coffee unless you have phoned ahead several days in advance. This will then allow your beverage provider enough time to obtain a herd of Elephants, feed them several kilos of coffee berries and then wait for the digestive process to complete. Sort through the piles of dung for the coffee beans, roast , grind and you’re ready to brew. If space is an issue, as Elephants do take up space in any room, you could use Civet cats instead. I’d advise against that as we all know cats are evil. And their poo really smells.

I digress.

Today your coffee shop offers wi-fi as well. And that’s what can be hazardous to your computer. Here’s why.

Microsoft released it’s latest set of patches, so called Patch Tuesday, this week. This particular update is noteworthy and requires immediate action on your behalf.

Within the list of updates are

  • MS15-011 & MS15-014 which harden group policy and address network access vulnerabilities that can be used to achieve remote code execution (RCE) in domain networks.
  • MS15-014 update addresses an issue in Group Policy update which can be used to disable client-side global SMB Signing requirements, bypassing an existing security feature built into the product.
  • MS15-011 adds new functionality, hardening network file access to block access to untrusted, attacker controlled shares when Group Policy refreshes on client machines.

Remember our coffee shops, its collection of Elephants, Cats and wi-fi? Here’s the attack scenario as described by Microsoft.

MS15-014 Attack

This is an example of a  ‘coffee shop’ attack scenario, where an attacker would attempt to make changes to a shared network switch in a public place and can direct the client traffic an attacker-controlled system.

  1. In this scenario, the attacker has observed traffic across the switch and found that a specific machine is attempting to download a file located at the UNC path: \\10.0.0.100\Share\Login.bat .
  2. On the attacker machine, a share is set up that exactly matches the UNC path of the file requested by the victim: \\*\Share\Login.bat.
    1. The attacker will have crafted the contents of Login.bat to execute arbitrary, malicious code on the target system. Depending on the service requesting Login.bat, this could be executed as the local user or as the SYSTEM account on the victim’s machine.
  3. The attacker then modifies the ARP table in the local switch to ensure that traffic intended for the target server 10.0.0.100 is now routed through to the attacker’s machine.
  4. When the victim’s machine next requests the file, the attacker’s machine will return the malicious version of Login.bat.

You can find more detail here http://blogs.technet.com/b/srd/archive/2015/02/10/ms15-011-amp-ms15-014-hardening-group-policy.aspx

All of updates from Microsoft are available in ZENworks Patch Management. If you can’t see them, just perform a subscription download to make sure you have the latest content.

Feb 10 Patch Tuesday

You  deploy these updates in the usual manner. I’d also recommend that you look at using patch policies that will make keeping on top of Patch Tuesday a lot easier for you.

To further protect your device estate, you should look at having security settings that can adapt to the location. ZENworks Endpoint Security allows you to define policies whose enforcement settings change depending on the location of the device. For example, the Firewall can be less restrictive on known networks but have increased restrictions for those that are unknown. You could force use of VPNs in those pesky coffee shops.

I should make it clear that ZENworks can do nothing about rogue Elephants sitting on a laptop or a cat doing something worse.

 

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