Improving your Telegram Security

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Telegram’s user continues to increase and recently it reaches 400 million user per month

Since its birth, there are many features added plus friendly API allowing various innovative ideas add-in to its base. 

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But, having lots of features may also result in lots of possibilities for hacking. One of the many features that may be wrongly used is the Automatic Media Download. 

As noob @ beginner, many do not realize it until their phone or PC slow due to disk space has shrunk as telegram keeps on automatically download all files. 

The most scarier is that the auto-play anything including GIF, video, and audio. All this can be used by hackers to insert a code and inject it upon executed/run by telegram.

However, luckily telegram allow us to modify the setting. Here are the steps to change it:

1. Go to your telegram setting and choose Advance

Telegram setting window

2. At the Advance screen, go to Automatic media download section

In the Advance setting

3. Click In private chats

In automatic media download setting

4. In the setting, click all the slide-tick to disable it (or you can choose whichever you want to enable or disable). You can even reduce the size to increase the protection rate.

5. Continue the process for all settings within the Automatic media download section.

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That’s all.. you are ready to go and you shall be safe.

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Tableau Public - Apple Mobility Data and Dark Mode

I've been working on 2 visualizations. 1 is based on Apply Mobility Data and the other is based on edited Sample Superstore.

Check it out here.

Mobility Data based on Apple's mobility data.

Grid on Dark Mode based on Tableau Sample Superstore (edited version)

All visual is available at https://public.tableau.com/profile/nurul.haszeli.ahmad#!/

All dataset is available at data.world @ https://data.world/haszeliahmad/data-analysis

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Parameter in Tableau - Using available Dimension with additional 'All' for all data

I am writing (and still writing as of this article) a manual to assist me in teaching Tableau. One of the sections is Parameter. There are many examples and guidance provided by Tableau.

You may read/view the following articles/videos for the guide on parameter.

1. https://interworks.com/blog/interworks/2012/03/26/how-to-create-and-use-parameters-in-tableau
2. https://help.tableau.com/current/pro/desktop/en-us/parameters_create.htm
3. https://help.tableau.com/current/pro/desktop/en-us/changing-views-using-parameters.htm
4. https://www.youtube.com/watch?v=CrfEJ24FWpQ
5. https://www.youtube.com/watch?v=rJsaezoTVAE
6. https://www.youtube.com/watch?v=opfVV1maNVw

The only problem I faced was to have an 'All' data if the user did not select any or wishes to see all data. None of them help. I tried using Action and Filters, yet it only shows based on selection and all show nothing.

That is until I found this solution.

IFNULL([FilterField],’Null’) = IF [Paramter] != ‘All’ THEN [Parameter] ELSE IFNULL([FilterField],’Null’) END

In a more readable, it will be like this

IFNULL([FilterField],’Null’) = (

     IF [Parameter] != ‘All’ THEN 

          [Parameter] 

     ELSE 

          IFNULL([FilterField],’Null’) 

     END

)

Step to:

1. Create your parameter - In this case, you use any Dimension as the Parameter by choosing a List and choose the list by changing the Fixed section and click on Add Values From.
2. Don't forget to add 'All' as one additional list
3. Drag the Dimension that you used as the parameter from the Dimensions Card into Filters Card.
4. In the Filter option, choose Condition and choose by Formula, and insert the above solution into the formula. 
5. Don't forget to change the [FilterField] to the Dimension used for the filter and the [Parameter] to your created parameter. 
6. Do ensure that 'All' is the same as your definition in the parameter (the character case and spelling is equal)
7. And that shall do it. You are ready to go.

Thanks to the person posted here: https://tarsolutions.co.uk/blog/tableau-add-an-all-to-a-parameter/

There are also an alternative solution to this and posted here: http://www.vizwiz.com/2012/09/tableau-tip-adding-all-filter-option-to.html

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Data Analysis - Use it !!

I was reading many developer's site and chat (telegram and whatsapp) when the government stated that they are looking for an app similar to Singapore apps to track the close contact of the Covid-19 positive patient.

In Singapore, they are using a technology which I presume is Bluetooth to ping close contact within the radiant of the tech and capture necessary data which then used to determine the contact and request them to perform screening. Here are some of the news:

1. https://www.thestar.com.my/tech/tech-news/2020/03/20/covid-19-singapore-launches-contact-tracing-mobile-app-to-track-coronavirus-infections
2. https://www.pymnts.com/coronavirus/2020/app-lets-singapore-track-virus-patients-movements/
3. https://www.nst.com.my/news/nation/2020/03/578445/smartphone-app-track-contacts-covid-19-patients
4. https://asia.nikkei.com/Spotlight/Coronavirus/Singapore-urges-citizens-to-sign-up-for-COVID-19-tracking-app

And the apps is available on Google Play and Apple Store

1. https://play.google.com/store/apps/details?id=sg.gov.tech.bluetrace&hl=en
2. https://apps.apple.com/sg/app/tracetogether/id1498276074

And as this article is written, there are many groups including international are coming with various hackathons for apps that can be used to track all COVID-19 patients and their close contact.

In Malaysia, since the announcement, many had gather groups to develop apps.

From my perspective, why must we reinvent the wheel? Why we need to develop many apps when we already have few that are potentially be used for it. 

For instance, D'scover by Favioriot was developed for a user to explore whatever the user likes but also close contact that uses the apps. I believed they can just tweak the apps to get close contact for COVID-19 and it is much faster than building and testing new apps. (by the way, this is not promoting them and I don't gain anything from it :))

Not just that apps, people have been using Google Maps, Waze, Grab, etc. All these apps collected millions of data and one of these data is people's location and whereabouts. On top of that, all telcos do have their customer's data location and track their movement. I attended the Big Data conference by Bigit a few years ago where one of the telcos presented their data analysis. They have shown the heatmap of their user and based on the communication tower.

I even had a discussion with a few telcos when they approach us (my previous company) to provide their services and wish for data sharing. I do request to have a set of data of their customer whereabouts too to ensure we can provide efficient services at the moment the customer approaches our station or hub, or at the time they are supposed to do so.

These data can be utilized to find close contact with COVID-19 patients. From these data, we know where they go, their ride and whom the came across with or pass by. Of course, these data are secured by all those companies for customer's safety and PDPA compliance. But, for the sake of government and to combat COVID-19, they can request minimal information limited to the phone number to call the respective COVID-19 contact. 

You just need a group of data scientists and data engineers to focus on the massaging and provide the relevant info to the government fast and secure. That's all :)

Don't REINVENT the wheel. Used It and MAXIMIZE the POTENTIAL.

* My personal opinion based on experience. Agreed to disagree :)

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Ontology Model for C Overflow Vulnerabilities Attack

Prepared the slide and was hoping to present at a conference. Unfortunately, due to Covid-19, it can only be shared online here.

I would like to thank all in the slide for making it through especially Saiful who give it all to complete the paper and published it at IJATCSE.

You may access and view the slide at Slideshare

Ontology model for c overflow vulnerabilities attack from Nurul Haszeli Ahmad

#covid19 #overflow #softwaresecurity #overflowvulnerabilities #programanalysis #staticanalysis #informationsecurity #security #cybersecurity

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