Security quotes of the week

[Posted November 11, 2015 by jake]

In modern computing, the terms "software", "firmware", and "hardware" relate to the types of no you'll get when asking for security patches.

— Jonathan Zdziarski (Thanks to Paul Wise.)

If we could trust userspace applications, we wouldn't need SELinux. But we assume that userspace code may be buggy, misconfigured or actively hostile, and we use technologies such as SELinux or AppArmor to restrict its behaviour. There's simply too much userspace code for us to guarantee that it's all correct, so we do our best to prevent it from doing harm anyway.

This is significantly less true in the kernel. The model up until now has largely been "Fix security bugs as we find them", an approach that fails on two levels:

1) Once we find them and fix them, there's still a window between the fixed version being available and it actually being deployed
2) The forces of good may not be the first ones to find them

This reactive approach is fine for a world where it's possible to push out software updates without having to perform extensive testing first, a world where the only people hunting for interesting kernel vulnerabilities are nice people. This isn't that world, and this approach isn't fine.

— Matthew Garrett

We mentioned that the AES key is generated locally on the victim's computer. We looked into the way the key and initialization vector are generated by reverse-engineering the Linux.Encoder.1 sample in our lab. We realized that, rather than generating secure random keys and IVs, the sample would derive these two pieces of information from the libc rand() function seeded with the current system timestamp at the moment of encryption. This information can be easily retrieved by looking at the file's timestamp. This is a huge design flaw that allows retrieval of the AES key without having to decrypt it with the RSA public key sold by the Trojan's operator(s).

— Bitdefender LABS finds a flaw in Linux "ransomware"

In my enormous to-read pile I've got "Why Johnny Still Can't Encrypt", and that's from fifteen years after the original paper on PGP's unusability was published. It's scary to think that companies like Apple have done more to protect us from intrusive government surveillance than nearly a quarter century of PGP has, because they've made it usable by the masses.

— Peter Gutmann

Security quotes of the week

Posted Nov 17, 2015 22:51 UTC (Tue) by ras (subscriber, #33059) [Link]

> t's scary to think that companies like Apple have done more to protect us from intrusive government surveillance than nearly a quarter century of PGP has, because they've made it usable by the masses.

Peter's right, of course. But it's interesting to see how these companies have done it. Instead raging against TPM's, TrustZone and TXT as tools of the media companies to control us all, they have used them as they should be used: to protect the secret that locks down the device, making it so expensive to extract not even the FBI bothers. And instead of raging at the injustice of preventing users from loading their own software on a device like the GPLv3 does, they use the idea of trusted code only running code coming from a trusted source to protect the average person from himself. Viruses are more prevalent on Android phones than iOS because Google allows people who think they know better to bypass that security.

And Peter is also wrong. It is true that Apple and Google have made us all more secure from retail attacks. (Retail attacks are those launch against a single device.) But in encouraging (forcing?) us to store data in the cloud, they have made us much more susceptible to wholesale attacks. Wholesale attacks are launched against a bottle neck all data flow through, and so if successful destroy the many people - not just one like a retail attack. Wholesale attacks are usually much harder to pull off, but the prize is so much bigger. I'm sure Google and Apple are subject to relentless court actions and political manoeuvrings by the law enforcement agencies for precisely that reason - the latest being the now retracted claim that secure communications enabled by Android and iOS enabled the Paris attacks.

Open source could provide a solution to this wholesale problem. It's a pity we allow out phobia's to stop us from addressing it.