Happy Holidays and Cameos Video – Vol 5

I probably won’t put out another post until the new year, so I’ll take this opportunity to wish everyone a happy holiday period, and I hope things will get better for everyone next year!

You may know I have a YouTube channel, and I include cameos of people saying “dot com” at the start of every video. Every now and then I put out a compilation of those clips, and here is volume 5, made up of the clips I used over this this last year.

Thanks to everyone who got involved. These clips are my favourite bit of the videos. πŸ™‚

Stay safe, and see you next year!



Video : Analytic Function Exclude Clause in Oracle Database 21c

In today’s video we’ll demonstrate the analytic function exclude clause, introduced in Oracle database 21c.

The video is based on the following article.

You might also find these useful.

The star of today’s video is Rene Antunez, who took a few of us to see the Pyramids of Teotihuacan when we were in Mexico on an ACE speaker tour.



ORDS, SQLcl, SQL Developer and SQL Data Modeler New Releases (21.4.x)

We’ve got some early Christmas presents!

I’ve updated my Docker and Vagrant builds to use the new versions of ORDS and SQLcl. You can see them here.

You can read Jeff Smith‘s announcement posts here, which include an overview of some of the new features.

Only the SQL Developer and Data Modeler releases were as a result the Log4j issue. They are client tools, so they are not really a threat, but it’s good to get the updates through so fast.

You have permission to open your presents early! 😁



Log4j Vulnerabilities : My Random Thoughts

For technical information keep checking the Apache Log4j Security Vulnerabilities page for updates.

Someone on Twitter asked me to write something about the Log4j issue and my response was I’m not really qualified to do that. After some consideration I thought maybe my uneducated opinion would be useful to others, so here goes…

Basic Context

This is a variation of something I wrote on an internal P1 incident, to give people some context. Remember, there are a range of people reading this P1, so it was written to be understandable to a wide audience.

  • Log4j is an open source library used for logging in many Java applications. If you are not using Java apps, you are not using Log4j, so you are safe. If you are using Java apps, the vendor may not have used Log4j to do logging. This is why it is important to scan servers and check with the vendor to see if their software is vulnerable or not.
  • This is not an issue with Apache HTTPS Server. Apache is a software foundation, which manages many commonly used open source software products, including the Apache HTTP Server. When you see “Apache Log4j”, the word “Apache” is a reference to the software foundation, not the HTTP server. As a result, it’s not safe to assume that if you don’t use Apache HTTP Server you are safe.
  • Client applications running on your PC are low risk compared to server applications. Most of the attacks are based around sending requests containing dodgy payloads to application servers. Your local PC applications don’t handle such requests, so are extremely unlikely to be affected. They should still be patched as soon as patches are available, but you don’t need to obsess about them.

Here’s a quick summary:

  • Not a Java application. Don’t worry.
  • Java application that doesn’t use Log4j. Don’t worry.
  • Java application that uses Log4j 1.x. Don’t worry about these vulnerabilities. Of course, older code may be susceptible to other vulnerabilities.
  • Java application that uses Log4j 2.x. Java 8 (or later), upgrade to Log4j release 2.17.1*.
  • Java application that uses Log4j 2.x. Java 7, upgrade to Log4j release 2.12.4*.
  • If upgrading Log4j is not an immediate option, maybe you are waiting for a vendor to release a patch, consider mitigations until upgrades are possible.

* These versions were correct at the time of writing. Keep checking the Apache Log4j Security Vulnerabilities page for updates.

Mitigations are not Solutions

Upgrading Log4j is the only way to be sure.

  • Java 8 (or later) users should upgrade to Log4j release 2.17.1.
  • Java 7 users should upgrade to Log4j release 2.12.4.

In the early days of the vulnerabilities, most people focused on mitigations. Probably the most common was to add this JVM parameter.


Or to set this environment variable.


These worked for the initial vulnerability, but don’t stop all attacks. They are listed as “discredited” on the Apache Log4j Security Vulnerabilities page. It’s still worth doing this while you wait for patches from vendors, but this only limits your exposure. It’s not a complete fix. Do not do this and assume it’s game over!

Another option was to remove the JndiLookup.class completely. This is still listed as a valid mitigation if you are not able to upgrade. It may seem scary, but if a vendor patch is not forthcoming, you need to weigh up the risks.

zip -q -d log4j-core-*.jar org/apache/logging/log4j/core/lookup/JndiLookup.class

In addition to the direct mitigations, you also need to consider the bigger picture. Applications that are available to the outside world are clearly at enormous risk. If applications are only available inside your company network, then the risk is reduced. I’m not saying ignore internal applications, but prioritise the higher risk systems first maybe?

Which of my systems are at risk?

If you work in a mixed shop with lots of 3rd party products, that is not necessarily an easy question to answer. You can’t just search the file system for *log4j* and think that’s good enough. The log4j libraries are often deployed inside other JAR files or zip files.

I’ve been using the log4j-detector tool by MergeBase to scan servers. They’ve been releasing new versions regularly since this issue started. It seems to work well, but I’m sure other tools are available.

On Linux servers all my software is under “/u01”, so I scan like this.

java -jar /tmp/log4j-detector-2021.12.22.jar /u01

I don’t have many Windows servers, but here’s an example of a command I used to scan an Artifactory server. Notice it’s not a standalone Java installation on this server, but one shipped as part of Artifactory.

"E:\jfrog\artifactory\app\third-party\java\bin\java.exe" -jar log4j-detector-2021.12.22.jar E:\jfrog

I would suggest you scan systems, even if your Vendor says they are safe. You never know what additional software has been installed by someone.

Log4j Developers

I’ve read a number of comments where people have criticised the Log4j developers, and for the most part I think they are totally out of order. The vast majority of companies have no engagement with open source software. They don’t commit code, and they don’t donate money to the projects they rely on. If you are just taking without giving anything back, I feel like you are not in a position to complain.

I understand some of the criticisms from a technical perspective, but hindsight is a wonderful thing. You could have spent time looking through the source code and highlighted stuff you didn’t like, but you didn’t. You could have got involved, but you didn’t.

I suspect there are developers of other common libraries checking their code for “exotic” features that need to be turned off by default…

Open Source

I’ve seen some people using the recent Log4j issues as a way to attack open source on a more general level. If people couldn’t see the source, they wouldn’t find the exploits right? I don’t buy this. Security through obscurity is not security. I wonder how much longer these vulnerabilities would have existed if the source code was not freely available?

Vendor Reactions

The reaction of vendors has been really interesting. Some have been really quick to react. Some, not so much. At times like this it’s really important that vendors release a statement as soon as possible, even if that is a message that says they are aware of the issue and are investigating. Your typical “watch this space” message. If your vendors were slow to react, or didn’t react at all, then I think you need to question whether you should be working with their products.

This is true for vendors of products that don’t even use Java. In addition to scanning, we have been compiling statements from vendors regardless of their technology stack. For a vulnerability this high profile, I think it’s important all vendors release a statement. It may sound ridiculous to you, but not every person involved in the process has a grasp of what technology stack is used by each product. If a vendor provides a clear statement, then it makes life a lot easier.

Oracle Advisory

The Oracle advisory came out pretty quick, and has been updated frequently over the last week as more patches have been released. Keep an eye on it over the next few days, as I expect some existing patches will be reissued with Log4j 2.17.


You still need to use your brain when determining the risk. The Oracle database is marked as not vulnerable, but there are some items shipped with the database that use vulnerable log4j versions. For example SQL Developer is shipped with the database, but this is a client tool. It is not receiving HTTPS requests from users, so it’s not a threat. There are patched versions of this available, but do you care? In a similar manner Enterprise Manager is vulnerable, and you should patch it, but it shouldn’t be accessible publicly, so the threat is lower. The chances are only your DBAs have firewall access to this server, so it represents a smaller threat than a public facing application server.


It has been a shit show, and there are little signs of it calming down much before Christmas, but you have to use this as a learning experience. Please apply patches as soon as they are available. If your vendor is slow off the mark, apply the mitigations while you wait.

As I’ve said, I’m not an expert, just someone trying to cope with these issues. If you see anything you think is factually incorrect, please tell me so I can correct it.



Video : Analytic Functions Groups Clause in Oracle Database 21c

In today’s video we’ll demonstrate the analytic functions groups clause, introduced in Oracle database 21c.

The video is based on the following article.

You might also find these useful.

The star of today’s video is a certain well known virus, knitted by the wife (Debra Lilley). This is what social isolation has done to her. πŸ™‚



Bringing new life to an old MacBook Pro

I’ve got an old MacBook Pro (13-inch, Mid 2009) that sits next to my bed. I use it for watching films and streaming rain sounds while I sleep. It stopped getting OS updates a while ago, and more recently it doesn’t want to play Prime videos, so I figured it was time to take action.

It’s got a Core 2 Duo processor, 8G RAM and a 500G SSD, so it’s not great, but it’s more than capable of doing what I need it to do…

I would like to say I did a lot of research to decide the best OS for it, but that would be a lie. I figured I wanted Ubuntu, and I wanted to run a simple window manager, so I picked Ubuntu Mate.

  • I downloaded the ISO to my Windows 11 desktop.
  • Used the Portable Apps version of Rufus to burn it onto a USB stick.
  • Put the USB stick into my old MBP.
  • Restarted the MBP and held down the “alt” key to give me the boot menu, and picked the USB stick.
  • The live version of Ubuntu Mate started and I clicked the install icon.
  • A few questions later and I had a running Ubuntu Mate installation.

The first problem was I didn’t have wifi access, so I had to plug directly into my router to get internet access. I installed a suitable driver for my wifi card, did an update and I was ready to go. If I had read the installer pages properly, I could have loaded the proprietary drivers as part of the install, but randomly clicking the “Continue” button without reading is the way I roll. πŸ™‚

I installed KeePassXC and DropBox to get access to my passwords, and that’s about it. It’s working really well, and saved me having to think about what to replace the old laptop with.

So my current operating system landscape looks like this:

  • My main workstation is a Dell XPS laptop running Windows 11.
  • I also have a MacBook Pro 15-inch on my desk running macOS Big Sur, which I use to stream films while I work, and test my Vagrant builds on macOS.
  • I have a server running Oracle Linux 7, which I tend not to use much these days as my XPS laptop has more than enough power to do most things I want to do in VirtualBox VMs.
  • I have the old MacBook Pro 13-inch next to my bed running Ubuntu Mate.

I believe in operating system diversity… πŸ™‚

I know people become fanboys/fangirls/fanpeople of their operating system of choice, but I really can’t be bothered with all that anymore. I used Red Hat Linux, then Fedora as my main desktop for 10+ years. I spent a few years with macOS as my daily driver. Now I’m happily using Windows. I’m not even that partisan about my Linux distros these days. I use Oracle Linux for all my Oracle software, but I’ll use any Linux distro for non-Oracle stuff. It’s all the same but different… πŸ˜‰



Video : Analytic Function Window Clause in Oracle Database 21c

In today’s video we’ll demonstrate the analytic functions window clause, introduced in Oracle database 21c.

The video is based on the following article.

You might also find these useful.

The star of today’s video is Peter Scott, who took time out of his life of luxury in France to say “.com” for this video. πŸ™‚