I needed to send an encrypted file to a user with a Mac. They were unable to install additional software on their machine, and I have no Mac to verify things on.
By default Mac’s roll with openssl installed (thanks Google), so the solution seemed to be to use that.
You can debate the encryption algorithm choice and substitute as appropriate. But the basic syntax for encryption and decryption using AES-256 is shown below:
Note: again this command will prompt for the password to be entered before extracting.
Warning; running with scissors
This is securing with a password. Go big or risk exposure here. Someone could always try brute force and you want to make sure that takes way way longer than the validity of the information you are protecting. I recommend 72,000 characters long as a minimum to be sure.
Now you have a key distribution problem though. How to get the password to the other person securely? You cannot email them the password since this is the same delivery mechanism for my scenario.
Generally WhatsApp (or other end to end encrypted chat client to a mobile phone) is good.
Phoning and saying a long password can be awkward but works (so long as they promise to eat the paper they write the password on immediately).
SMS is less secure but still verifies that the user is in possession of that person’s phone.
Little bit of charity – The #BoycottYourBed charity was raising money for Action for Kids. The idea was simple; go sleep someplace other than beds in your home. I could not get the kids to focus on the live stream. Because they were too excited about a massive den that was being built to sleep in. It came to a sticky conclusion when a kid prodigiously vomited over much of the den… So.. I scrubbed, cleaned, and then relocated to the kids room on the floor in a snuggly pile. Until that point it was probably the most fun the kids have had in months.
Back to School – The return to school has been amazing. They were so bored at home for such a long time that no amount of amusement seemed to do. Now we are having a much happier kid and much better weekends together since everyone isn’t knackered.
Adventures Outside – We made it to the park together at weekends because, as I said, everyone wasn’t totally knackered by my days off. It has been a long lock down and a struggle to get everyone outside at the same time. This was very good. More of this.. oh. whoops its winter. The leaves are falling 😀
10k steps rolling on every single day – All the way back to Christmas Eve 2019. Some seriously… Seriously tough days in August. Early in the month Kid A succumbed to food poisoning and I basically didn’t sleep for 7 days while sitting up with them. But here I am another month more into this stupid goal!
TV – Ashes to Ashes – What a show. It has taken quite a while to re watch but it is such an excellent programme. That ending is absolutely sublime and you should not read the rest of this blog post if you have not watched Life on Mars and Ashes to Ashes. Drop whatever you are doing and start watching them. They really pay out.
Audiobook #1 – Rama II by Arthur C Clarke – Listening to the first one has really lit up my brain for thinking about the cosmos again. Getting the second one the moment the first one ended to continue the story was *obvious*. This time we are given characters and tension based on them interacting which is interesting. The first one now seems like some idyllic jaunt now by comparison. Very entertaining.
Audiobook #2 – The Garden of Rama – In for a penny eh? Straight into the 3rd part. Anything at this point is probably spoilers.
Gaming – Rise of the Tomb Raider was this months PS Plus title. I devoured that. I like single player titles with a story. It basically was like “tomb raider does Arkham Asylum”. The mechanics are all giving off super batman vibes. That is a good thing because it is possible to play stealthily. The game says I have approximately 97% completed it. Given that is based on collectables that are not on the map I am considering is it really worth walking every area to go further? After completing games they should just mark things on maps in vague areas with circles to search in.
The bad
Had a bit of a panic attack over the last weekend of August. As before the triggers seem clear. Not sleeping well again and having rather a lot of things going on at the moment. Even when the things are awesome and well worth it. It is still a reminder to get more sleep.
Highlight of the month
Work highlight: I delivered a job and got some amazing feedback from the customer. Never underestimate the value of feedback (positive, and negative). Be kind, stay constructive. Other than that tell everyone all of the things all of the time!
Life highlight: I said I couldn’t sleep right? I made a stupid short film because I was asked to make a single monstrous slice of toast. I mostly wanted to document the horrible slice of toast existed.
Ever wanted to use 3rd party python libraries when making a Burp Extender? I had somehow avoided it until recently.
Warning: Be aware before pasting in the commands below that I think they configure your new pip environment and store all dependencies inside a new folder within the current directory.
There I was finding a lovely Cross Site Scripting (XSS) vulnerability in a customer site today. Complete beauty in the HTTP 404 response via the folder/script name. So I started to write that up.
I peered at the passive results from Burp Suite and noticed a distinct lack of a vulnerability I was expecting to see:
I looked at the HTTP headers and saw this peering back at me:
X-XSS-Protection: 1; mode=block
Burp was correct not to raise that issue because it detects where that very header is insecurely set or non existent.
For the uninitiated the “X-XSS-Protection” header is supposed to tell web browsers to inspect content from the HTTP request which is then present in the immediate response. It had a laudable goal to make reflected XSS a thing of the past, or at least harder to exploit.
Chrome liked it so much it defaulted to having it enabled. Even if the server didn’t bother setting it. This caused much consternation.
Stawp making the world safer Google… Jeez!
I thought ah this is my testing browser (Firefox) I must have overridden the XSS filter.
So I try in Chrome.. *pop pop*.
So I try in Edge.. *pop pop*.
I think I google “Is X-XSS-Protection still a thing?” and stumble across this nugget:
No. It is not a thing. Has not been a thing for a little while.
The modern approach is to ensure that you use robust Content-Security-Policy settings. The radical approach is to prevent XSS by secure coding practices which will just never ever catch on.
Security tools and scanners including: nikto, burp suite, and nessus all still pull this header out as something to be reported on. Does it have any real relevance if user-agents simply ignore it now?
It may impact older browsers. But generally when you are talking about any web browser that is old. There will be some way to completely control the victim’s computer. Logically you should only concern yourself with where the herd is running at today.
My approach is to take this out the back to put it out of its misery with a few rounds through the head(er). Then I will stuff it and mount it onto my wall next to “Password Field with autocomplete enabled”. Which is itself deprecated based on browsers also choosing to ignore it.
Time rolls on and standards change. Lets have a round of applause for good old “X-XSS-Protection”. It has been a good sport. A brilliant contender but sadly it never truly saw its potential realised because Arsenal kept buying replacement wingers. It never got any game time.
10k steps rolling on every single day – I have worked in a few jogs a week this month to get the heart rate elevated more regularly. It comes with the obvious benefits for doing so. My resting heart rate has gone down around 6 BPM which isn’t to be sniffed at.
Calorie Calculator – I know what helps me to lose weight. My level of activity has been fine but really the key is to stop ingress of breaded or cakey items. In lockdown my cupboards suddenly got flooded with tonnes of food because the uncertainty of delivery slots made us guess what was needed for a week+ at a time. In the general meh mod alcohol went up, food went in, and the natural impact was weight gain. For the last week of July I went back to tracking calories. A process I find so dull it unilaterally stops me snacking.
Bid on houses – I have always wanted a house with a garden. I was not fortunate enough to grow up with that and it is something I clearly aspire to. Lockdown certainly made me not want to wait anymore so co-incidentally when the market opened in Scotland again I went to view a property. I bid on it but it went for silly money beyond the valuation (50k or so more). The positives are that we got familiar with the process, someone came and valued our place, and I spent a long weekend cleaning and now love my flat more.
DIY in the flat – With a house move unlikely it means I get to focus on the flat some more. I hung some blinds in the kitchen which stops the massive stream of sunlight in the morning taking the sting of the sun out. We have also sought some quotes to finally tackle the horrible part of our flat – the central heating plumbing. Since we will be here for a few more years most likely I don’t want to go into another winter with the kids bedroom being cold. Also finally being able to decorate after this would be amazing.
Reading/Audiobooks #1 – I completed White Fragility by Robin DiAngelo over many morning walks in June and early July. The biggest revelation to me was how we allow “racist” to be so narrowly defined. It is conflated to mean “is a bad person” and to mean discrete individual acts of hatred which are both intentional and overt. Really we can deal with those incidents as being perpetrated by assholes. We pat ourselves our backs for not being those guys. While remaining oblivious to the underlying societal problems. Thought provoking read. Well worth an audible credit.
Reading/Audiobooks #2 – Several people have recommended the subtle art of not giving a fuck by Mark Manson. It is entertainingly written. It however feels like “bro” science and thus far seems pretty obvious to me. Don’t care about the things you cannot change. Pick your battles. Rather than saying anything new it appears to be a love note to tell you to not bother with any self improvement techniques at all. But look at me. Accusing something of merely being snide by being snide. It has helped more people than I could ever hope to. There has been some bits encouraging me to think about some of my choices. Not an absolute train wreck, but I was not bowled over.
Reading/Audiobooks #3 – Randevous with Rama by Arthur C Clarke. A legend of a friend of mine recommended it. I have been entirely captivated by this and it represents a triumphant first fiction book of 2020.
Gaming – I completed the Last of Us Part II. It is hard to say you “enjoyed” it unequivocally. Because I think if you are doing it right this game is toying with you the player. The narrative arc has a few fixed set points where you MUST behave in a certain way. In an otherwise open world you simply MUST do some questionable things to proceed. They are not glorified though they are horrific. To survive the post apocalypse you have to develop emotional calluses which first means taking a few bruises. THIS IS AMAZING. Any thrill for vengeance was totally and absolutely wrung out of me before the final act.
Gaming #2 – I fired up the original XCOM game from way back in 1994. This game has captivated me most summers since 1994 and I give it a play through in a couple of evenings. It is an absolute classic.
Work – A customer project saw me do an architecture review. I really enjoyed it. It has been a while but I was just in love with the full adoption of Devops/Secops/Psyclopses/Containers etc. So many of the tools and technologies required to make something which starts secure are free and relatively easy to use. What a time to be alive?
Music – I ordered a new practice amp from Positive Grid before lockdown. It took 4 months to arrive. The product has been fun and I have not had more than an hour to play with it. I can easily see how this would help me improve my playing by giving me automatic backing tracks to learn to solo over. I have put the day back but now it may be the time to learn scales instead of the “by feel” approach I have. Humans implicitly hear the bum notes. So you can cobble together what sounds right without formality. Just eventually I guess I should grow up and learn the instrument!
Music #2 – as a satire on the need to run Doom on any device or it hasn’t been “hacked” I did this moments after getting it out the box :D. The tone is a default one on the amp I don’t think I used the app to get that. It makes some gorgeous tones.
— ℙ𝕒𝕦𝕝 ℝ𝕚𝕥𝕔𝕙𝕚𝕖 🏴 (@cornerpirate) July 25, 2020
The Bad
End of July blues. While the month was running along very positively it hit Thursday 30th and suddenly I was just completely “meh” about life. I didn’t get to sleep on time on Wednesday finally getting about 4h30m sleep according to my tracker. Add into the mix that I was calorie counting and it is probably just a huge energy dip.
I am not overly concerned since a day of being depressed when you are better at recognising why is probably a sign of progress.
Did you know that Dr Who has no officially been back in production longer than it was taken off air? The tipping point was July 2020. The Glasgow Dr Who meetup group were looking to celebrate that fact socially distanced so I knocked that monster out in a wonderful 30 minutes or so. Fun but it was way pasta my bedtime to do it.
Moving about – 10k steps achieved again! Every day since Christmas eve 2019. Some days it has been exceptionally difficult. Still.. Clinging on to this one achievement belligerently. I did do a few mornings of light jogging to improve the heart rate zoning so probably better than last month. Otherwise the quality of the movement is pretty low.
Content – A blog post! – Like an actual one about technical stuff that is hopefully useful. Mainly about development but shows some of the impact of a pentest report landing and making wild claims about how simple it is to just patch things. I like to try and replicate responding to a report. It helps me make better recommendations which have a dash of empathy when I know it is going to be an absolute pain to implement.
Decorating – bought a new TV stand, threw out a tonne of things and made the living room look infinity nicer. Much better for the psyche looking at nice clean walls. Lockdown seems to have prevented me buying accessories for trunking I am looking at. So I will have to wait to finish the basic human level of decoration I want. But as I said infinitely better. Following a philosophy of doing one thing a weekend at the moment.
Gaming – Completed Uncharted 4 – Obviously an excellent title. Discovered that there was Uncharted: The Lost Legacy for extra stories which I am working on now. Also a great game. Last of us Part II came in and I am absolutely loving it so far. 5 hours in I realised the last 5 games I have played have all been NaughtyDog. They seem to be cornering the single player story genre.
Security Research – I worked for several days on my tools RDPUpload and RDPDownload with the blessing of my employer. Both came out of projects I have worked on but I took the time to formalise them and put them in a blog post. If you see the highlight of the month you can also see I pushed myself to publish it perhaps a bit earlier than they were ready. The official work blog and tool release hasn’t happened yet though.
The Bad
Panic attack. First one since early February. Despite everything that has been going on in the world I have remained amazingly unfazed. It goes on to prove that my particular problem is a lack of sleep. After the kids stopped going to bed before 10pm for a solid couple of weeks I had a sudden panic attack at 2am and couldn’t get to sleep. It had less of an impact than previous bouts, but I was still knackered for a day or two after.
Result: Going to bed for a few nights in a row when the kids did instead of sitting up to get some adult media content time. Not the wholesale changes to lifestyle I was managing at the start of the year. But I have definitely let all the things I was doing go during lockdown.
Highlight of the month
Talking to the beautiful people at Abertay Hacksoc. I had been doing research and making tools to release a blog post for work. When asked to speak to the students on the Monday I said “lets do it!”. It led to a panicked two days trying to make some content and a practical demo. Here is part of the talk via a tweet:
In this blog post I discuss how I migrated an old Netbeans project (Specifically ReportCompiler) to retrofit Maven and to integrate OWASP’s dependency check into the build process.
I made ReportCompiler a long time ago (long enough that Java was a sane choice). It is in no way complete and has adorable missing or half implemented thoughts throughout it.
It will import “.nessus” XML files and various other vulnerability scanners too. I use it mostly as a Nessus viewer since my gripes with the UI experience in browser are legion. I have a love affair with it in particular though because it has saved me an unbelievable amount of time over the years even accounting for the initial intense development time.
I do not use it every day like I used to and so the project is only lightly supported by me.
Getting up and running
Open up netbeans (I originally designed the GUI in this so it kind of needs to be netbeans unless another GUI editor works just as well?).
Create a new “maven” project.
Copy the source code from your previous project into the source folder.
Deal with any package renaming because of this movement. They will be highlighted in red at the top of every class file.
Check import statements for warnings. Each underline here points to a dependency we will need to include using maven now.
For each import error copy the package name for example “org.python.util.PythonInterpreter” and google it with the word “maven”. This will find the package that you need to import. For example:
Google Hacks Confirmed!
Clicking on the top result will show you the information about the relevant maven package:
Found Jython Package
Notice that in this example the latest version was newer as highlighted. Click on the newer version. Then copy and paste the “<dependency>” tag into your projects “pom.xml”.
After adding each dependency build the app again and watch that import statement fix itself. Repeat until all the red underlines have vacated your project.
Given the age of ReportCompiler there were a few deprecation warnings around the use of Vectors etc. I did not massively feel the need to redo the code for that since it has Vectors in pretty much every single area of the application. Now I feel the developer pain. Some day the rug will be pulled but for now we are golden. Vectors survive for now.
By the end of this my application compiled and executed. The only thing that did not seem to work was the resources folder including the risk icons. I wrapped the code loading these icons in a “try catch” statement to see a more verbose error message and to ensure the app loaded despite the wonky icons.
Bundling the app and dependencies into a single Jar
To fix the wonky icons I needed to ensure the resources were included inside the Jar file or otherwise copied during the build. The simplest route I found was to use the “maven-assembly-plugin”. Adding this to the “pom.xml” file resulted in a self-contained single jar file with all resources:
In my new project the image icons were located under the “src/main/resources” folder. Maven tutorials all say this is where to put them:
resources folder
To access these resources I modified my code to use “getClass().getResource()” as shown:
try {
this.critical_risk_icon = new ImageIcon(getClass().getResource("/critical-icon.png"));
this.high_risk_icon = new ImageIcon(getClass().getResource("/high-icon.png"));
this.medium_risk_icon = new ImageIcon(getClass().getResource("/medium-icon.png"));
this.low_risk_icon = new ImageIcon(getClass().getResource("/low-icon.png"));
this.info_risk_icon = new ImageIcon(getClass().getResource("/info-icon.png"));
this.no_risk_icon = new ImageIcon(getClass().getResource("/none-icon.png"));
this.computer_icon = new ImageIcon(getClass().getResource("/computer-icon.png"));
this.show_highlights = showHighlights;
} catch (Exception ex) {
ex.printStackTrace();
}
Terrific. Now the risk icons were loading beautifully.
Integrating OWASP’s Dependency Check
The reason I was moving to maven was to add sanity into the dependency management. The version of ReportCompiler to date was stuck with whatever jar files I downloaded back when I wrote the project. I consoled myself with the fact that none of the code is remotely accessible which reduced the threat profile.
But here was a Pentester clearly not practising what they preach. Yelling “patch all the things” by day while my barn was on fire. This gave me an opportunity to experience life from the other side of the fence for a bit. Which we should all practice regularly.
OWASP’s Dependency Check does an excellent job of listing known vulnerabilities in dependencies. I have tried it out in a few different contexts over the years and wholeheartedly recommend it to customers. It will not solve security problems on its own. But it will highlight easily fixable weaknesses from third party libraries.
I added this to my “pom.xml” to add it into my build process:
The goal was set to “check”. In this configuration dependency-check runs when the application is built and an HTML report will be created in the target folder next to my jar file. You can set the build to halt if risks over a certain CVSS score appear which I would recommend for an actively maintained project which is mission critical.
Below is an example report kicked out during a build with some CVE’s to show:
Dependency-Check Report Containing 55 known vulnerabilities
I went through all my maven dependencies and ensured the most recent releases were included (or so I thought). By running “clean and build” again the vulnerabilities related to Apache POI disappeared. Partial success!
My “pom.xml” did not point specifically to any of the remaining vulnerable libraries meaning that they were most likely “dependencies of my dependencies”. I shook my fist at the sky and cried out about how the supply chain will always get you.
I found that netbeans will draw a handy dependency graph. In “Project” view expand the “Project Files” folder and click on “pom.xml” and then on the tab labelled “Graph” along the top to see this:
Netbeans POM.xml dependencies graph
I could now throw shade at “docx4j” 6.1.2 which was build with Apache Commons Compress version 1.12 when version 1.20 is available. On looking into this 6.1.2 was nowhere near the latest version of “docx4j”! There were newer ones with slightly different names available. Hot swapping that out solved the “apache-commons-compress” related CVEs.
The most recent maven release of “docx4j” (version notes for 11.1.8) was compiled with several outdated dependencies. Unfortunately “jackson-databind-2.9.9” was included and vulnerable to 26 known CVEs. There was no danger of fixing this soon and it would most likely require opening a ticket on the docx4j project.
Drilling into the others I found that “jexcelapi” had a vulnerable version of “log4j” as shown in the graph below:
Log4j 1.2.14 baked into jexcelapi
Looking into it the project for “jexcelapi” was no longer supported since it was last released in 2009. A prime candidate for being entirely replaced. A quick google found that Apache POI is the new hotness. I cutout the old library and went for something that was supported.
At the end of this process I had tried my best but ended up with vulnerabilities via docx4j’s jackson-databind dependency. C’est la vie.
Fixing vulnerable Dependencies is Hard
After thinking about it I can see four ways to proceed with fixing all known CVEs in my dependency chain:
Do I really have the most recent release of my dependency? Look up the actual project’s page and see if there is a later release.
Can I contact the maintainer and get them to update their public build with the newer dependency baked in? This would fix the issue and eventually filter back into the maven ecosystem. Probably need to do that for docx4j.
Do I need that dependency? If it is a minor feature and you are all up to date maybe you can remove the feature or implement it another way. As per jexcelapi.
Can I build my own version which is secure (recompiling with the latest libraries)? However, this instantly breaks the mavenness of the dependencies
Now I imagine what it is like when a Pentest report lands heartlessly saying “update your dependencies”. It is clear that this is still a tricky problem in 2020.
This is the end
That was the end of the process. The application compiled and had the same bugs it had before but now had more up-to-date dependency management. Folks may now be more inclined to contribute to the project, and I am more inclined to support it.
Hopefully you found something of value in the tale.
Activity – 10k steps… every day.. Going all the way back to Christmas Eve 2019. I have brought an old treadmill back into service during lockdown. I go outside for a decent walk a couple of times a week.
Uncharted Games – the remastered 1-3 and 4 have all been given out for “free” with PS Plus over the last few months. I have waded my way through 1-3 and am onto 4. They tell really fun stories even if I find the shooting a bit repetitive at times. The puzzles are often worth it.
Life on Mars/Ashes to Ashes – if you have not seen LOM/A2A before then I envy you because you have a hell of a ride to go on. I encourage you to do so.
Security Research#1 – Work gave my team an opportunity to take on security research against some open source projects. We had a lot of fun and found a tonne of vulns that we are in the process of disclosing.
Security Research #2 – I had time to implement a process for data exfiltration using QR codes (RDPDownload). This is the opposite of my RDPUpload tool that I made a few years ago. While not a brand new technique I enjoy building exfiltration tools to see the trade offs involved and yes this worked on a genuine project. I am working on releasing that tool this month.
Decoration – Given lockdown makes me stare at my walls I realised I am not in-love with my flat anymore. I have gone on a programme of doing a minor bit of decorating every night for two weeks. Filling holes here. Sanding and painting there. While I am no expert at this the results are sufficient to mean my eye isn’t drawn to various defects that were driving me mental. The benefits of this for mental health has been huge.
Audiobooks – I was unable to get through any in May 😦
The Bad
In 2019 I was immobilised for months and was unable to get out of the house. I gained a lot of weight as a result and felt like crap. Indeed the whole point behind this “Captain’s Log” series was to show the positive steps I was taking to avoid a repeat of that period of my life and to get physically and mentally fitter.
Under lockdown my mental health has remained robust. By the end of May I decided to weigh in to discover indeed I had put on all the weight I had lost pre-lockdown. Not shocked but it is also a little annoying.
Kids out of their routine == Cranky days, late nights, and early waking.
When you are not sleeping right then weight gain is basically inevitable. Fortunately, the kids have started to sleep more regularly in the last week. So light at the end of the tunnel.
Highlight of the month
I think the decorating has really been the highlight. While there is still absolutely tonnes to do. It feels positive like I have stopped treading water and gone on to exert control over my domain. Plus I guess it provides a bunch of exercise to get it done which helps generally with everything.
I managed to continue to walk 10k steps every single day in April. It is hard going given the lockdown and most days I do them entirely indoors. It is like the last feature of my exceedingly healthy start to 2020 that I am maintaining.
I needed to use RDPUpload in April and took an evening to patch it for Python3 and introduce some new functions. An equivalent tool to exfil through locked down remote environments was also made but not public facing yet. It felt great to get a bit of on message content out again 😀
My work runs a regular Hackathon event where we share skills and do some collaborative research. It went great and let me help out with a bunch of potential CVEs that could take sometime to get disclosed. I do love this stuff as it is things I never really did elsewhere.
Music has been the saving grace of my lockdown. It lifts the spirit like nothing else.
Keyboard – I bought one before Christmas 2019 and struggled to get time on it until the lockdown. I was able to practice chord shapes and play a bunch of songs out of a chord song book in early April. Even getting as far as coordinating left and right hands together to sort of double up the chords for a richer sound. To be clear; I have no idea what I am doing but it is fun to try!
Guitar – I taught myself to play around 20 years ago but finding time to keep up has been a struggle since having kids. In 2018-2019 I started to get into home recording and I have seen myself practising those skills in the lockdown.
MPD218 & Ableton – This cheeky wee bit of kit lets you assign sounds to buttons and manipulate them. I had given Ableton software a brief go in 2019 but it didn’t make a whole lot of sense. With the arrival of the MPD I sat through a bunch of Ableton tutorials and made a simple dancy track. My intention is to figure out how to make drum tracks on this setup which I have never done before.
My friend was making a video to demonstrate CVE-2020-7055 (an RCE in the WordPress Elementor plugin). It was a bit stark at 3 minutes of silence so I battered out something that felt appropriate over lunch. In the end I gave it to someone else in my team to make something more professional sounding which went on the final video. But I have been listening to what I made on loop for a bit and it isn’t as shit as I initially thought!
Glasgow Defcon (DC44141) went online for the first time via Twitch. With talks from @ZephyrFish (an intro to Red Teaming) and @InfoSec_Paul_M (on blue team phishing detection techniques). While on the stream someone said “toss a coin to sysadmin” so that inspired this 😀
The DC44141 meetup had the pub vibe via an open Discord chat room after the talks. Featuring lots of lovely people.
Brooklyn 99 season 6 on Netflix arrived and was consumed to much joy.
A feature length Red Dwarf episode arrived and was absolutely a joy to behold. I truly appreciate having spent so long of my life in the company of those characters.
I played counter strike: GO more often with great people and had a good time. I feel like I suck a lot less than last month. The game is free on Steam if you want to get hold of it. I have a dedicated server and share the details if you DM on Twitter to @cornerpirate.
I started Half Life 2 Updated which I think is free on Steam. I loved HL2 obviously. This updated version seems to have different or more immersive music and I was in absolute tears of joy about how amazing the feat of engineering that is. They introduced GRAVITY for the first real time into games and had an absolute blast making puzzles. It is inconceivable now that games were not like this before. Truly brilliant and if you haven’t played it in over a decade like me, if not now when?
This month’s audiobooks
How to talk so little kids will listen by Joanna Faber & Julie King. I had not completely finished this in March and eventually got through this by mid April. It was a great book with tonnes of advice for communicating with kids clearly. Sadly the lockdown has regressed most peoples behaviour because we are trapped in pretty tight quarters. Still several of the techniques have reduced the impact of that.
Amazon Web Service by Paul B Richie. I am looking to learn more about AWS and Azure to have more rounded knowledge in those fields. I know bits and pieces but am seeking a few more jigsaw pieces. I am going to be honest. I haven’t gotten far into this and the initial chapter was like listening to someone reading a dictionary rather than inspiring the listener. Ok ok.. I also selected this book in particular because the author is almost my name sake. It might not be fit for the purpose I had in mind.
The Bad
The amount of crud I am eating is essentially putting on the weight I lost at the start of the year. Now that I am getting towards adjusted to the new lockdown reality I have been able to start reigning that in.
Highlight of the month
This has put a smile on my face. I needed to go and collect medicine. When I wrote in to say I was going AFK. An amazing colleague said “A QUEST!” just before I went out the door I recorded a few bits of the walk.
When I got home I strung them together and threw some music on it. There is now a channel in youtube “Fun with cornerpirate” which maintains a list of two quests so far:
The audio of me speaking is particularly bad because of the wind. When I filtered it out in Audacity using noise reduction it left my voice sounding shrill.. Lesson learned even if it is spur of the moment take out the better microphone which has the fuzzy stuff on it.
I now have the right mic but the wrong app was the lesson from episode two.
A tool which works in Linux and Windows which will “upload” a file to an RDP or other remote session where copy and paste or drag and drop are disabled.
This is a very old technique. All I have done is have a stab at making my own tool for doing this. I meet aspiring hackers who say they want to jump into coding, but don’t have any “ideas”. They seem unimpressed when I say write a port scanner.
If that is you then I say to you: re-invent the damn wheel!
Sometimes the wheel needs upgrading you know? Many of the tools we have now as the “goto” for something are about 17th in newness of technique. Any tool can be toppled by a better successor.
But world domination is not the goal. Implementing your own versions of old ideas is actually just for getting your skills in for the day you invent an entirely new wheel. It also teaches you how a thing works which is brilliant. At a job interview you will stand out if you actually know what the top tool does under the hood.
What I learned on this one
To make rdpupload I have learned:
argparse better (I have used this before)
how to simulate key presses in python
how to do a progress bar in a CLI
how to zip a file using python
how to play an mp3 in python (though it didn’t work on Windows, yolo).
But most importantly I learned how a file upload may work by typing it, along with how to decode that on the server side easily.
Technique Used
The following summarises the techniques used:
Attacker Side:
Zip the file you want to upload (might save some characters depending on the file).
Base64 encode that file (so every character we are going to use is available on a standard English Keyboard).
Split the encoded file into chunks of size 256 characters (arbitrary length choice here).
Spoof a keyboard typing each block of 256 characters until it is completed.
Display a progress bar and optionally play the sound of a typewriter hammering away while the “upload” happens.
Victim Side:
Place the cursor into “Notepad” within an RDP session.
When the “upload” is complete save that as a “.txt” file.
Open a command prompt and use “certutil.exe” to decode the base64 encoded file. The syntax for that is shown below.
Use the zip feature of Windows to unpack the zip file.
Profit.
The decoder on the server side relies on “certutil.exe”. Unless I am wrong this is available from Server 2003 upwards so is pretty useful for most use cases.
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