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Entries from April 2014

OpenSSL "Heartbleed" bug: what's at risk on the server and what is not

A few days ago, a critical bug was found in the common OpenSSL library. OpenSSL is the library that implements the common SSL and TLS security protocols. These protocols facilitate the encrypted tunnel feature that secure services – over the web and otherwise – utilize to encrypt the traffic between the client (user) and the server.

The discovery of such a security bug is a big deal. Not only that OpenSSL is very common, but the bug that was found is one that can be readily exploited remotely without any privilege on the attacker’s side. Also, the outcome of the attack that is made possible is devastating. Exploiting the bug allows an attacker to obtain internal information, in the form of memory contents, from the attacked server or client. This memory space that the attacker can obtain a copy of can contain just about everything. Almost.

There are many essays and posts about the “everything” that could be lost, so I will take the optimistic side and dedicate this post to the “almost". As opposed to with other serious attacks, at least the leak is not complete and can be quantified, and the attack is not persistent.

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Bitcoin does not provide anonymity

When people discuss Bitcoin, one of its properties that is often considered is its presumable anonymity. In this respect, it is often compared to cash. However, it shall be recognized and understood that Bitcoin is not as anonymous as cash; far from it, actually. Its anonymity relies on the concept of pseudonyms, which delivers some (unjustified) sense of anonymity, but very weak anonymity in practice.

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