Top posts

Every blog post that took off on Hacker News, ranked by the votes of its best submission. 679 posts.

Security & Privacy
2025
631

Cell Phone OPSEC for Border Crossings

I have heard stories of more aggressive interrogation of electronic devices at US border crossings. I know a lot about securing computers, but very little about securing phones. Are there easy ways to delete data—files, photos, etc.—on phones so it can’t be recovered? Does resetting a phone to factory defaults erase…

636

Towards a test suite for TOTP codes

Because I'm a massive nerd, I actually try to read specification documents. As I've ranted ad nauseam before, the current TOTP spec is irresponsibly obsolete. The three major implementations of the spec - Google, Apple, and Yubico - all subtly disagree on how it should be implemented. Every other MFA app has their own…

657

Entropy Attacks

The conventional wisdom is that hashing more entropy sources can't hurt: if H is any modern cryptographic hash function then H(x,y,z) is at least as good a random number as H(x,y), no matter how awful z is. So we pile one source on top of another, hashing them all together and hoping that at least one of them is good.

658

Belgium Is Unsafe for CVD

This post is about the reason I will probably never try to warn any organisation in Belgium about any vulnerability again. Recently I have been dealing with an attempt at coordinated vulnerability disclosure (CVD) with an organisation in Belgium. This post is not about that, because I’m not allowed to write about it…