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Matthew Green

@matthewdgreen.bsky.social

I teach cryptography at Johns Hopkins. https://blog.cryptographyengineering.com

17,217 Followers  |  400 Following  |  1,517 Posts  |  Joined: 28.04.2023  |  1.8374

Latest posts by matthewdgreen.bsky.social on Bluesky

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AI propaganda is here, and this is only the beginning. Exactly as I predict in my book. A Chinese (apparent) subcontractor, is reportedly using AI combined with massive data collection and analysis to run targeted influence operations. www.nytimes.com/2025/08/06/u...

09.08.2025 14:57 β€” πŸ‘ 55    πŸ” 30    πŸ’¬ 7    πŸ“Œ 2
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That’s exactly what they want. Project 2025 explicitly calls for shutting down foreign social media like WeChat and TikTok. (Trump’s implementation is more of an attempt to force their sale than a shutdown.) There is a strategic goal aimed at political stability; it’ll just be their politics.

09.08.2025 14:13 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Project 2025: What a second Trump term could mean for media and technology policies | Brookings Roxana Muenster analyzes Project 2025’s plans for technology, media, and communications policies and the implications for existing policies.

The Heritage Foundation does hate LGBTQ. But they also have a document that talks about amassing power and crushing every opposing power center in the United States. These two things aren’t mutually exclusive. www.brookings.edu/articles/pro...

09.08.2025 14:09 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

I think there’s a vanguard of people who really just hate porn. I think the reason they’re getting so much deep support is because other more thoughtful people behind them see the implications of an unchecked Internet as bad, and view this as one (legislative and technical) tool to end it.

08.08.2025 21:03 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 1    πŸ“Œ 1

so the stupid canadian age verification bill is back in parliament so call your local MPs and tell them it’s bad and why it’s bad and don’t be ashamed to pander to them based on if they’re a tory or grit or otherwise - if you frame it in a way that mirrors their ideology, they might remember better

08.08.2025 15:10 β€” πŸ‘ 672    πŸ” 359    πŸ’¬ 15    πŸ“Œ 18

I admit it sounds a little looney tunes when I write it down that way and yet, we live in a looney tunes time.

08.08.2025 17:28 β€” πŸ‘ 10    πŸ” 1    πŸ’¬ 3    πŸ“Œ 0

For the ninth time I’m going to repeat my personal conspiracy theory that every democracy is fighting a battle to control its Internet against foreign influence, and β€œage verification” is not being pushed so hard because kids, but is actually one weapon being deployed for that fight.

08.08.2025 17:28 β€” πŸ‘ 52    πŸ” 8    πŸ’¬ 6    πŸ“Œ 0
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It Looks Like a School Bathroom Smoke Detector. A Teen Hacker Showed It Could Be an Audio Bug A pair of hackers found that a vape detector often found in high school bathrooms contained microphonesβ€”and security weaknesses that could allow someone to turn it into a secret listening device.

The Halo 3C is a smoke/vape detector that Motorola sells for use in school bathrooms. It also has microphones inside.

A teen hacker found them at his school, and with another security researcher has now shown they could be hacked for audio surveillance.

www.wired.com/story/school...

08.08.2025 13:47 β€” πŸ‘ 128    πŸ” 53    πŸ’¬ 4    πŸ“Œ 9

Just sitting here with an unfinished algorithm for solving MLWE all I need is that one missing piece.

07.08.2025 23:51 β€” πŸ‘ 29    πŸ” 0    πŸ’¬ 3    πŸ“Œ 0

OpenAI continues to deny me GPT-5 presumably because it knows I’ve got a list of prompts that will break all cryptography if it’s 8% as good as Sam Altman says.

07.08.2025 23:49 β€” πŸ‘ 203    πŸ” 10    πŸ’¬ 11    πŸ“Œ 2

I’m saying this because I had to switch back from book writing (fun! easy! still harder than many things I’ve done) to research paper writing, and it’s so much slower and more intricate. And I’m not even the lead author doing the hard stuff.

07.08.2025 15:51 β€” πŸ‘ 13    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

And a lot of the time the difference between β€œgood” and β€œbad” science is the kind of laziness that’s just Tuesday in software development.

07.08.2025 15:50 β€” πŸ‘ 13    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

You’ve got a field that basically involves obsessive people doing obsessive work for relatively terrible pay and then you’re like β€œI, as an expert in JavaScript development, demand that every result be replicated.” I mean ok that would be cool, but how and with what resources.

07.08.2025 15:49 β€” πŸ‘ 11    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0

Anyway, I just want to be clear that I’m not patting anyone on the back. I’m just saying that this is absurdly more work than most other things people could be doing, for such a relatively small result. I think about this when people criticize science (often rightly) for lack of replication etc.

07.08.2025 15:47 β€” πŸ‘ 7    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

One of the things that amazes me about scientific research is how much work goes into it. It’s just crazy. I mean all things require work, but it’s just so far above anything else (writing, software development.) I understand all the complaints about replication, what’s missing is the labor.

07.08.2025 14:53 β€” πŸ‘ 63    πŸ” 5    πŸ’¬ 4    πŸ“Œ 0
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Jury deadlocks on money laundering charge against founder of crypto 'mixer' Tornado Cash A U.S. jury deadlocked on Wednesday on money laundering and sanctions evasion charges against the founder of Tornado Cash, a firm that makes cryptocurrency transactions harder to track.

Jury deadlocks on money laundering charge against founder of crypto 'mixer' Tornado Cash reut.rs/45t4KVJ

06.08.2025 17:05 β€” πŸ‘ 14    πŸ” 10    πŸ’¬ 0    πŸ“Œ 2
Meteor

Yes we did some work on this. It’s great, but then you need to make sure the LLM cover traffic isn’t weird. meteorfrom.space

06.08.2025 13:46 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Yes but it’s really easy to have AI generate stuff that β€œlooks good” if you’re using the wrong definition of β€œlooks good”, but might be really easily detectable. I guess maybe the real recommendation is that defenders need to think like censors, too.

06.08.2025 13:44 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

I agree that scale is going to be an issue for them, I don’t think you’ll have a transformer processing every packet. I do think you could build an architecture that’s heavily adaptive and uses filtering rules developed by gen AI.

06.08.2025 13:24 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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"How the Great Firewall of China detects and blocks fully encrypted traffic." is IMO the first glimpse into what this looks like, though.

The thresholds in Ex1 smell like something written by a decision tree and then adapted by humans.

06.08.2025 13:21 β€” πŸ‘ 18    πŸ” 6    πŸ’¬ 2    πŸ“Œ 0

Yes. It illustrates that (1) they care, (2) they’re happy to automate, (3) they’re operating at like .001% of the potential capability they could implement.

06.08.2025 13:23 β€” πŸ‘ 7    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

It also doesn’t help that DOGE cancelled a bunch of NSF grants working on censorship-evasion tech because they contained the keyword β€œcensorship.”

06.08.2025 13:20 β€” πŸ‘ 13    πŸ” 0    πŸ’¬ 2    πŸ“Œ 0

I don’t have anything wise to say about this. I just believe there’s a huge amount of room to lock down national Internet connections in ways that are going to be hard to bypass. It’ll come as a surprise when it happens and it would be better if we were thinking about it now rather than later.

06.08.2025 13:19 β€” πŸ‘ 13    πŸ” 3    πŸ’¬ 1    πŸ“Œ 0

A lot of the tools we have for evading censorship work on the principle that nobody’s looking too closely, and when they get clever and use steganography it’s only a little bit clever; the bar is very low to sneak past the tools that exist today.

06.08.2025 13:17 β€” πŸ‘ 9    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

And maybe it will stay that way for β€œbusiness reasons” but technically it’s due for a massive upgrade thanks to the new capabilities AI will be able to throw at network traffic in the next few years.

06.08.2025 13:14 β€” πŸ‘ 10    πŸ” 0    πŸ’¬ 2    πŸ“Œ 0

This is a field that’s been working for years to find clever ways to sneak traffic across China’s Great Firewall or out of Iran, and I think it’s become accustomed to a very lazy and mostly human adversary.

06.08.2025 13:13 β€” πŸ‘ 17    πŸ” 1    πŸ’¬ 2    πŸ“Œ 0

So I don’t like to generalize big conclusions from a few random conversations, but I feel like the censorship-evasion field of research is about to get clobbered by AI.

06.08.2025 13:11 β€” πŸ‘ 45    πŸ” 4    πŸ’¬ 3    πŸ“Œ 1
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How I feel every time I visit X.

06.08.2025 00:19 β€” πŸ‘ 42    πŸ” 4    πŸ’¬ 4    πŸ“Œ 0

To give you a sense of how bad the GOPs current polls must be. Indiana is already heavily gerrymandered and there are two Democrats out of 9 seats.

05.08.2025 23:53 β€” πŸ‘ 598    πŸ” 177    πŸ’¬ 32    πŸ“Œ 4

β€œI gotta be honest, the whole thing is pretty nuts,” says JHU CS’ @matthewdgreen.bsky.social. β€œMy best hypothesis is the phones are seeing a Wi-Fi access point that is slightly off from where they are.”

05.08.2025 13:28 β€” πŸ‘ 7    πŸ” 6    πŸ’¬ 0    πŸ“Œ 0

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