Here is the pdf slides of my presentation about Meltdown, the security vulnerability. First are full slides, then real presentation slides (with stops when asking questions/pausing and pondering). Free for re-use, but nice to cite.

This version is just full slides, with no interruptions.

This version is slides with …

This is a writeup for the Endless Christmas challenge, md5 hash 866c92038d6e9fc47db4424f71f6167a (download binary). It appeared in the X-MAS CTF, and it's a Reverse challenge.

Using afl with Radare we can see there are calls to write and execve, both happening in main, a sign that this program creates (and …

One of the very few things I learnt in art class is what the role of Jackson Pollock was in his art. Because, we were asked, what is the role of the artist, if the only thing he does is let paint drop on a canvas? His role is to …

After spending two months in Cork, Ireland, I feel like I can provide good advice for a nice day tour in Cork. I stayed in July-August, so some of my comments may be affected (by good weather, mostly). Here is the photo album of the whole time.

I think the …

If you are a tech company, and your people commit code, then you probably have some code review policy. And if you do not, you definitely should: you want to have an extra pair of eyes on the code that goes live. You certainly do not want a mistake to …

Make sure to add them in active code. Adding a spare php file with the WP-CLI command definition in /wordpress won't work, because that code won't be loaded by WP. Dropping the file into wp-content/plugins won't work as well. Make it part of an active plugin, or use your …

A small tale with a topological soul, with the aim of providing a very high level intuition for the notion of density and dense set in topology.

Smally Open was a cheeky youngster of the Open family who lived in a large meadow. It was a very nice and green …

Some months ago, I changed one link in the menu in my website postpaycounter.com. After that, it looked to me more people were purchasing products, i.e. the conversion rate had increased. But how to check whther that was really the case, or if it was just an accident …

During a Computational Vision lab, while comparing histograms, I stumbled upon a peculiar behavior. The histograms pairwise kernel matrix - which is just a fancy name for the matrix holding histograms correlations one with another - did not have ones on the diagonal. This means that one histogram was not fully correlated …

This was the final project for the Data Semantics course at university - A report on distributional semantics and Latent Semantic Analysis.

Here is the nicely-formatted pdf version (with references).

What is the Distributional Hypothesis

When it comes to Distributional Semantics and the Distributional Hypothesis, the slogan is often "You shall …

I was to reverse a file for a challenge, MD5 hash 85c9feed0cb0f240a62b1e50d1ab0419.

The challenge was called mio cuggino, purposefully misspelled with two g letters. It asks for three numbers. The challenge led me to a brute force of the password with a Python script, learning how to interact with a …

The scope of this article is to present the one time pad cipher method and its biggest vulnerability: the many time pad attack.

The one time pad: what it is and how it works

The one time pad is the archetype of the idea of stream cipher. It's very simple …

For a challenge in a university security class, I was given this file to crack: reverse1. I started with reverse0, which was considerably easier than the second one. In this post I will briefly explain how I tackled reverse1. I provided the files so you can you try on your …

Need to convert a base 10 integer in a base 2 one? Or, at any rate, convert a number from one numeration system to another? In Ubuntu, the bc utility already integrates these features. It is usually already installed, so you don't have to anything special.

Simply run bc, and …

Well, I have been wondering about this for quite a while now, and I have tried to run some tests to better understand what's going on under the hood. The standard answer is that after you call delete you should not expect anything good from accessing that memory spot. However …

What follows is Javier Silva's interview to me. The interview is mostly focused on how what it is like to be a freelance in the IT field and how to start as a programmer (and how that may evolve into a business). It was first published on his blog in …

With the Anspress theme/plugin, using the WordPress native function url_to_postid() on a question permalink returns the page ID of the base page. For example,

url_to_postid( "www.website.com/questions/question/this-is-the-question");

would return the page ID of the /questions page.

To get the WP question ID of this-is-the-question, use …

This add-on plugin for bbPress will allow anonymous users to subscribe to topics and get email notifications when a new reply is posted. The notification email includes an unsubscribe link.

bbPress notifications will keep to go out to registered users, this plugin only extends the thing to anonymous posters as …

This article aims at presenting a method for computing the relevance of a given string (pattern) in a text. This algorithm is at the core of my WordPress plugin Smart Tag Insert.

First of all, there is a difference between a simple pattern matching and computing text pattern relevance. The …

On December 2016 I purchased the System76 6th gen Lemur. These are more of impressions than a real review, but may be helpful if you're interested in buying a new laptop and were considering the new System76 Lemur. This is the review of the laptop released in December 2015. I …