Terence Eden. He has a beard and is smiling.

Terence Eden’s Blog

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Your Password Algorithm Sucks

· 18 comments · 600 words · Viewed ~1,942 times


Sorry but you password must contain and upper case letter, a number, a haiku, a gang sign, a hieroglyph, and the blood of a virgin.

There are two sorts of people in the world; those who know they are stupid and those who think they are clever. Stupid people use a password manager. They know they can't remember a hundred different passwords and so outsource the thinking to something reasonably secure. I'm a stupid person and am very happy to have BitWarden generate and save fiendishly complex unique passwords which are then…

What is a "Cyber Attack"?

· 4 comments · 750 words · Viewed ~507 times


Screenshot showing a journalist's incredulity at a report.

Terminology is hard. Computer terminology is even harder. Humans are animals who just love to classify things. We have a fundamental need in our delicious meaty brains to put things into conceptual buckets. This, I think, leads to some unfortunate consequences when our categories don't match up with other people's categories. For example, take this news story and this journalist's response to…

That's Not How A SIM Swap Attack Works

· 5 comments · 850 words · Viewed ~1,248 times


A padlock engraved into a circuit board.

There's a disturbing article in The Guardian about a person who was on the receiving end of a successful cybersecurity attack. EE texted to say they had processed my sim activation request, and the new sim would be active in 24 hours. I was told to contact them if I hadn’t requested this. I hadn’t, so I did so immediately. Twenty-four hours later, my mobile stopped working and money was wit…

FobCam '25 - All my MFA tokens on one page

· 3 comments · 1,000 words · Viewed ~1,014 times


A padlock engraved into a circuit board.

Some ideas are timeless. Back in 2004, an anonymous genius set up "FobCam". Tired of having to carry around an RSA SecurID token everywhere, our hero simply left the fob at home with an early webcam pointing at it. And then left the page open for all to see. Security expert Bruce Schneier approved of this trade-off between security and usability - saying what we're all thinking: Here’s a guy w…

The least secure TOTP code possible

· 4 comments · 750 words · Viewed ~5,209 times


QR code.

If you use Multi-Factor Authentication, you'll be well used to scanning in QR codes which allow you to share a secret code with a website. These are known as Time-based One Time Passwords (TOTP). As I've moaned about before, TOTP has never been properly standardised. It's a mish-mash of half-finished proposals with no active development, no test suite, and no-one looking after it. Which is…

What's the best way to protect banking apps on Android?

· 10 comments · 1,700 words · Viewed ~925 times


A tiny lego Storm Trooper eats a chocolate coin.

Lots of people using banking apps on their Android phones. They're a convenient way to check your balance, transfer money to people, and get alerts about fraudulent transactions. But, like anything related to money, they can be abused. Nowadays, thieves are not only snatching phones, but forcing their owners to transfer money to the thieves. This is not an isolated incident. How can you…

A decade later, has my mobile security advice changed?

· 7 comments · 1,750 words · Viewed ~356 times


Logo for 361 degrees podcast.

A decade ago, I appeared on the 361 Podcast to give my advice about mobile security. This was the era of the iPhone 5 and Android KitKat. BlackBerry was trying to have (yet another) resurgence and Nokia was desperately trying to keep Windows Phone alive. What advice did I give then, and is it still relevant? Stay Sceptical In at number five is just stay sceptical. I mean, quite often, lots…

Bank scammers using genuine push notifications to trick their victims

· 9 comments · 550 words · Viewed ~14,994 times


`In app popup. "Are you on the phone with Chase? We need to check it's you on the phone to us. Let us know it's you and enter your passcode on the next screen. @ Not you? Your details are safe. Just tap 'No, it's not me' and we'll end the call."`

You receive a call on your phone. The polite call centre worker on the line asks for you by name, and gives the name of your bank. They say they're calling from your bank's fraud department. "Yeah, right!" You think. Obvious scam, isn't it? You tell the caller to do unmentionable things to a goat. They sigh. "I can assure you I'm calling from Chase bank. I understand you're sceptical. I'll…

I can't use my number pad for 2FA codes

· 10 comments · 400 words · Viewed ~5,185 times


Computer number pad with the number 7 in the top left.

This has to be the most infuriating bug report I've ever submitted. I went to type in my 2FA code on a website - but no numbers appeared on screen. Obviously, I was an idiot and had forgotten to press the NumLock button. D'oh! I toggled it on and typed again. No numbers appeared. I switched to another tab, my numbers appeared when I typed them. So I was reasonably confident that my keyboard was…

What the UK Government gets wrong about QR codes

· 12 comments · 700 words · Viewed ~862 times


A leaflet for Childcare with a prominent QR code.

One of my most memorable experiences in the Civil Service was discussing link shortening services with a very friendly person from the Foreign and Commonwealth Office. I was trying to explain why link shortners like bit.ly and ow.ly weren't sensible for Government use. They didn't seem to particularly care about the privacy implications or the risk of phishing. I needed to take a different…

I made a mistake in verifying HTTP Message Signatures

· 5 comments · 400 words


A pet cat typing on a computer keyboard.

It's never great to find out you're wrong, but that's how learning and personal growth happens. HTTP Message Signatures are hard. There are lots of complex parts and getting any aspect wrong means certain death. In a previous post, I wrote A simple(ish) guide to verifying HTTP Message Signatures in PHP. It turns out that it was too simple. And far too trusting. An HTTP Message Signature is a…

O2 UK's Weird MSISDN Lookup API

· 7 comments · 250 words · Viewed ~221 times


Sorry, we don’t recognise this number. Please try again.

It's always fun keeping your network inspector tab open. While looking around the O2 UK website, I found this page all about eSIMs. For some reason, it wants to know the user's phone number. I put in a random number, and it refused to let me in. Putting in a genuine O2 number let me through. So what is it doing to validate numbers? It is making an API call to this URl: …