$3k Bug Bounty - Twitter's OAuth Mistakes

by @edent | # # # # # | Read ~10,424 times.
A Twitter login screen. Highlighted is the information that it cannot access your DMs.

Imagine the scenario. You're trying out some cool new Twitter app. It asks you to sign in via OAuth as per usual. You look through the permissions - phew - it doesn't want to access your Direct Messages. You authorise it - whereupon it promptly leaks to the world all your sexts, inappropriate jokes, and […]

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Major sites running unauthenticated JavaScript on their payment pages

by @edent | # # # # # # | 9 comments | Read ~23,442 times.
HTML code from Spotify.

A few months ago, British Airways' customers had their credit card details stolen. How was this possible? The best guess goes something like this: BA had 3rd party JS on its payment page <script src="https://example.com/whatever.js"></script> The 3rd party's site was hacked, and the JS was changed. BA's customers ran the script, which then harvested their […]

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Should you use SRI for self-hosted scripts?

by @edent | # # # | 2 comments | Read ~196 times.

Here's a curiosity which I found while stumbling through the Sony PlayStation store. The website loads internally hosted scripts using SRI (SubResource Integrity). Why? Does your work require you to swipe an ID card to access the building? That seems pretty normal. Does your work also remind you to keep your badge visible, and to […]

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Dynamic JavaScript and SRI

by @edent | # # # | Read ~160 times.
HTML source of The Guardian website. Polyfill is being loaded from their own CDN.

Some external JavaScript libraries are dynamic. That's a problem for the SRI model of security. How can this be fixed? Definitions Suppose I want my website to have the latest version of the jQuery library. I might use a Content Delivery Network (CDN) to serve the code for me. <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> If an attacker were […]

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Responsible Disclosure: CloudFlare - more interested in tracking than security

by @edent | # # # # | 2 comments | Read ~331 times.
A confirmation email asking me to click on a link,

CloudFlare claim they want to secure the web - but they seem more interested in tracking their customers than giving them decent security. Upon registering with the Internet giant, users are encouraged to confirm their email addresses. So far, so standard. This is the confirmation message CloudFlare sends out: Looks good! Hey! I wonder where […]

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Security issues on ArtChain

by @edent | # # # # | 4 comments | Read ~4,377 times.
A website with a popup notification.

One of the problems with the BlockChain goldrush is that it attracts a lot of people who don't necessarily have the required technical skill to safely run a service. This in turn reduces trust in the ecosystem. I'd like to discuss ArtChain.info - "Certifying Art Using the Bitcoin Blockchain" - and the some of the […]

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Responsible Disclosure - Citizens Advice Bureaux

by @edent | # # # # # | Read ~213 times.

A quick report into a nasty privacy vulnerability I found with the CAB. Unusually for me, this has no Internet component. Regular readers will know about my recent court visit. As part of that, I had to telephone the CAB Volunteers at the court who look after witnesses. I called, and was put on hold, […]

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Privacy, Security, & Ethics - Computer Science's "Jüdische Physik"

by @edent | # # # # # | 1 comment | Read ~215 times.
A fist emerges from a computer screen and punches the user.

I'm going to tell you an anecdote which is a gross oversimplification of a complex topic. In the early half of the twentieth century, certain physicists made breakthroughs in relativity, quantum mechanics, and nuclear energy. Many of these scientists were Jewish. The Nazis called these heretical ideas "Jewish Science" and suppressed their teaching. Jewish physicists […]

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Would you trust this ATM?

by @edent | # # | 3 comments | Read ~278 times.
A sign is taped haphazardly to an ATM. It warns people that the ATM is slow and may take a while to return their card. There is no branding on the sign.

Fake cash-machines are an increasing problem around the UK. Criminals attach all sorts of machinery - including fake fronts - to ATMs with the aim of stealing cash or card details. Wandering around Oxford yesterday, I noticed this sign attached to a bank's ATM: "This ATM is running slow and may take a while to […]

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Udacity Bug Bounty - or, please stop tracking every link in your emails

by @edent | # # # | 2 comments | Read ~364 times.
Clicking on the button shows an insecure web address.

Look, I know your company wants metrics. I know your boss wants to see the exact percentages of people who click on links in your emails. Your sales team are desperate to track conversions. Someone wants to optimise your funnel for reasons which are unclear to you, a lowly engineer. So you make the mistake […]

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