Stealing Data From Computers Using Heat

Security researchers at Ben Gurion University in Israel have found a way to retrieve data from an air-gapped computer using only heat emissions and a computer’s built-in thermal sensors. The method would allow attackers to surreptitiously siphon passwords or security keys from a protected system and transmit the data to an internet-connected system that’s in close proximity and that the attackers control. They could also use the internet-connected system to send malicious commands to the air-gapped system using the same heat and sensor technique. The proof-of-concept attack requires both systems to first be compromised with malware. And currently, the attack allows for just eight bits of data to be reliably transmitted over an hour—a rate that is sufficient for an attacker to transmit brief commands or siphon a password or secret key but not large amounts of data. It also works only if the air-gapped system is within 40 centimeters (about 15 inches) from the other computer the attackers control. But the researchers, at Ben Gurion’s Cyber Security Labs, note that this latter scenario is not uncommon, because air-gapped systems often sit on desktops alongside Internet-connected ones so that workers can easily access both. ...

March 23, 2015 · 1 min · 199 palabras · Nacho Cano

11 Ways To Track Your Moves When Using a Web Browser

some tracking methods do attempt to track the user over a long time, and in particular attempt to make it difficult to evade the tracking. This is sometimes done for advertisement purposes, but can also be done to stop certain attacks like brute forcing or to identify attackers that return to a site. In its worst case, from a private perspective, the tracking is done to follow a user across various web sites. Over the years, browsers and plugins have provided a number of ways to restrict this tracking. Here are some of the more common techniques how tracking is done and how the user can prevent (some of) it ...

March 15, 2015 · 1 min · 116 palabras · Nacho Cano

Exploiting the DRAM rowhammer bug to gain kernel privileges

“Rowhammer” is a problem with some recent DRAM devices in which repeatedly accessing a row of memory can cause bit flips in adjacent rows. We tested a selection of laptops and found that a subset of them exhibited the problem. We built two working privilege escalation exploits that use this effect. One exploit uses rowhammer-induced bit flips to gain kernel privileges on x86-64 Linux when run as an unprivileged userland process. When run on a machine vulnerable to the rowhammer problem, the process was able to induce bit flips in page table entries (PTEs). It was able to use this to gain write access to its own page table, and hence gain read-write access to all of physical memory. ...

March 14, 2015 · 1 min · 124 palabras · Nacho Cano

9 truths that computer programmers know that most people don’t.

Ever wondered why programmers are known as nightbirds? Why we stay up all night? Because it allows us to get into the zone, it allows us to focus on one thing and not have to worry about being interupted by someone - because they are all asleep. It’s a long stretch of the day where no one is up and no one is calling or trying to talk to us. It’s a great time to program, and think. ...

March 14, 2015 · 1 min · 83 palabras · Nacho Cano

How Video Game Breasts Are Made (And Why They Can Go Wrong)

If you’ve played games that have breast physics, you’ve probably seen how uncommon it is for games to show breasts that move like what they actually are: bags of fat affected by gravity. Instead, it’s more likely for a game to depict breasts as helium balloons that have minds of their own. Certain games have failed at rendering realistic breasts so widely that some people seem convinced that bad breast physics are the result of sexism, or of an industry that likes to objectify women. I’ve seen unfair conjecture about whether or not developers have ever interacted with real-life breasts. I’ve seen people imply that developers simply don’t know how to properly characterize women in games, and that gaming’s ocean of unrealistic breasts is what happens when we have so few women developing games. ...

March 12, 2015 · 1 min · 139 palabras · Nacho Cano

The greatest program ever written

I’m a programmer. I write games. Games programmers get a lot of respect, but none of them, not me, not Carmak, and not Abrash. None of them deserve the honour which I want to bestow on David Horne. This is because David Horne wrote the greatest program ever written: 1k chess on the ZX81. David Horne is not an urban myth. David Horne achieved what many would even now consider impossible. He wrote a chess game, with AI, that ran on a poorly documented, buggy machine that contained only 1k of memory. ...

March 8, 2015 · 1 min · 94 palabras · Nacho Cano

The MakeLisp Process

So you want to write a Lisp interpreter? Welcome! The goal of the Make-A-Lisp project is to make it easy to write your own Lisp interpreter without sacrificing those many ”Aha!” moments that come from ascending the McCarthy mountain. When you reach the peak of this particular mountain, you will have an interpreter for the mal Lisp language that is powerful enough to be self-hosting, meaning it will be able to run a mal interpreter written in mal itself. ...

March 8, 2015 · 1 min · 83 palabras · Nacho Cano

Attack of the week: FREAK (or ’factoring the NSA for fun and profit’)

A group of cryptographers at INRIA, Microsoft Research and IMDEA have discovered some serious vulnerabilities in OpenSSL (e.g., Android) clients and Apple TLS/SSL clients (e.g., Safari) that allow a ’man in the middle attacker’ to downgrade connections from ’strong’ RSA to ’export-grade’ RSA. These attacks are real and exploitable against a shocking number of websites – including government websites. » Matthew Green | blog.cryptographyengineering.com

March 5, 2015 · 1 min · 64 palabras · Nacho Cano

Computadoras imprescindibles

Gracias a la desbordante imaginación de una dama victoriana del siglo XIX pudimos dar el salto del cálculo a la computación. Ada creó el primer programa de ordenador en su mente, simulando una máquina que nunca existió. La informática nació dentro del cerebro de una mujer. » txipi | blog.txipinet.com

March 1, 2015 · 1 min · 50 palabras · Nacho Cano

Proving that Android’s, Java’s and Python’s sorting algorithm is broken (and showing how to fix it)

Tim Peters developed the Timsort hybrid sorting algorithm in 2002. It is a clever combination of ideas from merge sort and insertion sort, and designed to perform well on real world data. TimSort was first developed for Python, but later ported to Java (where it appears as java.util.Collections.sort and java.util.Arrays.sort) by Joshua Bloch (the designer of Java Collections who also pointed out that most binary search algorithms were broken). TimSort is today used as the default sorting algorithm for Android SDK, Sun’s JDK and OpenJDK. Given the popularity of these platforms this means that the number of computers, cloud services and mobile phones that use TimSort for sorting is well into the billions. Fast forward to 2015. After we had successfully verified Counting and Radix sort implementations in Java (J. Autom. Reasoning 53(2), 129-139) with a formal verification tool called KeY, we were looking for a new challenge. TimSort seemed to fit the bill, as it is rather complex and widely used. Unfortunately, we weren’t able to prove its correctness. A closer analysis showed that this was, quite simply, because TimSort was broken and our theoretical considerations finally led us to a path towards finding the bug (interestingly, that bug appears already in the Python implementation). This blog post shows how we did it. ...

February 28, 2015 · 2 min · 220 palabras · Nacho Cano