vx | systems | networks | security | prof @uc3m

Joined August 2012
The lyf so short, the craft so long to lerne. - Chaucer
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Juan Tapiador retweeted
After recently moving to the University of Oxford, I am currently recruiting PhD students in the broad areas of web systems, social computing and Internet measurements. If you know of anybody, please let them know to reach out (deadline 2nd December)!
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this is wild 🧐
While evaluating Qwen3.8-Flash-Next in a controlled sandbox environment, Cohere's research team observed something unexpected. Asked to generate a defensive cybersecurity detection rule, the model instead inventoried aspects of the machine it was running on and attempted to upload a probe file to an Alibaba Cloud storage bucket in Beijing. Notably, the model's reasoning trace stated that it would not invoke any tools before taking these actions. Cohere's sandbox blocked the attempt, and no external communication succeeded. We have not determined the root cause, and we are not asserting malicious intent. But the incident raises important questions for organizations deploying agentic AI systems: Can models take actions that differ from their stated reasoning, and how should security teams evaluate trust, provenance, and behavior in open-weight models? We are publishing our findings because organizations making model adoption decisions deserve as much information as possible. We hope this contributes to greater transparency, stronger security practices, and continued collaboration across the AI ecosystem. Read the full report: cohere.com/blog/concerning-b…
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Evil qwen
if you have a qwen3.5 4b around, please try steering neurons L14 N8949 +1 and L13 N7956 -1 now you have evil qwen recipe: dose × median(‖resid‖ leaving layer L, tokens 1:) / ‖W_down[:, n]‖` at the down_proj at every input
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Juan Tapiador retweeted
A mysterious threat actor has hacked more than 330 Tor servers earlier this month to carry out a mass-sniffing campaign against Tor users. The attacker hacked Tor relays, infected them with the Ebury Linux malware, and converted them to exit relays where it could intercept SSH connections and downgrade email connections to steal unencrypted email traffic. The hacking campaign went undetected for three days, between October 2 and 5, before it was spotted by a Swiss engineer and reported to the Tor security team. kaba.cx/posts/20261020_Tor/
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Juan Tapiador retweeted
Some stats on #php2shell. In the 10 hours before it was publicly announced, across the @Cloudflare network we saw thousands of attempts to exploit it. That jumped to tens of thousands in the 45 minutes post announcement, hundreds of thousands within 2 hours, and millions now.
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New paper on Android 16 security and AI agent orchestration to appear at PETS 2027!
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I've lost count of how many times the Wayback Machine has saved the day for me.
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Finding peer reviewers is getting harder.
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The back of the Navier-Stokes milestone shirt is the last line of the chain-of-thought from the solution:
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Juan Tapiador retweeted
13 years of tinfoil hats for srand48(time(NULL)
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Juan Tapiador retweeted
Try opening a Microsoft Word document from 1992, a Flash project from 2006, or a proprietary database dump from 2010. Half of it is unreadable binary rot. Now open a .c source file or a plain .txt file written on a UNIX PDP-11 in 1973. It opens in 0.001 seconds on every computer on Earth. Plain text is the only truly immortal data format humanity has ever invented.
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📢 Call for Workshop Proposals: IEEE EuroS&P 2027! Looking to organize a workshop in security & privacy? Join us in Madrid, Spain (July 5 & 9, 2027)! 🇪🇸 🗓️ Proposal Deadline: Oct 30, 2026 (23:59 AoE) Guidelines & Call For Workshops: 🔗 eurosp2027.ieee-security.org… #EuroSP27
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McKinsey CEO says AI has changed his hiring criteria. The consulting firm is looking more at people with degrees in “art, history, music” and prioritizing “folks better at novel creativity”.
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Juan Tapiador retweeted
Math is progressing by hours now, not years
We are publishing an update to OpenAI Problem #109 (integer multiplication) with a substantial further tightening: T(n) = O(n (log n)^(1 − κ)), With κ = 2⁻⁷⁸ (tightened from κ = 2⁻¹⁸²) Approximately 570 million fold improvement over our previous result and a 2¹⁰⁴ fold improvement over original OAI result. Our earlier ceiling applied to a cubic bottleneck in the network. The new witness scales quadratically; we haven't established a new ceiling. The key was using nonadjacent axis swaps to route around the cubic bottleneck. The original manuscript already supported nonadjacent axis swaps. Using them directly reduces layout routing from O(d²) to O(d) swaps.
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Juan Tapiador retweeted
made a rug for your desktop so you can sweep your mess under it
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[continued] I say "almost" because there is going to be one way to maintain secrecy. Software as a service with the executable hiding behind a network connection to the cloud. But as of now, we must assume that anything shipped as an executable, or even a firmware image, is as transparent as glass. It won't keep its secrets for any longer than it takes for somebody to be motivated to throw an LLM at it. I did not see this coming. When I wrote down the theory of open source, 30 years ago now, I thought closed source would be gradually driven towards extinction by cost gradients, but survive indefinitely in certain niches. I did not foresee it being wiped out in a technoapocalypse. Ironically, I thought one of the application areas in which closed source would persist longest was games. There are still some obstacles. In US law, decompilation of a binary is a derivative work of the binary that falls under whatever copyright it had. However, it is also settled law that if you decompile binary code to a precise specification of what it does, then generate fresh code from that without looking at the decompiled stuff, you're in the clear. This was the case law that allowed PC clones to exist, after Phoenix Technologies reverse engineered the original IBM PC BIOS. The two-step process - binary to specification to unencumbered code - will no longer takes a large number of programmers and years of development time. With an LLM, it's now a thing you can do in a day. Ubiquity will make it impractical to prosecute all the people who might skip the specification step. Source code can also be covered by patents. You can be able to see their source code for a patented technique and not be able to use it without violating the law. Linux has evolved practices for dealing with this problem - one is not shipping patented video codecs, but requiring you to download them as plugins from jurisdictions where U.S. patents can't be enforced. This presents patent holders with the impractical challenge of individually suing millions of end users, assuming it can even figure out who they are. To date, AFAIK, this has not been attempted. And that's about it. If there are any other ways left to retain software secrecy and lock-in than SaaS or patents, I can't think of any. Well, you could epoxy-pot a firmware ROM, I suppose, but that can be defeated with a heat gun and a dental pick. Device manufacturers will learn not to pay for an assembly step that has become useless. Forced migration from shipped binaries to tied cloud services will be tried - Adobe pioneered this, and Microsoft is pushing it as hard as they can given that their OS is a binary that has to run locally. Both companies are seeing massive user revolts over this. There is good reason to doubt that it's a strategy that can hold customers in the long term. Also, a lot of things can't safely be tied to the cloud at all, because they can't tolerate a random network outage. Machine tools, medical devices... A whole lot of proprietary software business models are going to collapse. Hard. One that I think might survive is tax software; being able to decompile it doesn't necessarily do you a lot of good because its actual value is tracking a ruleset that changes over time and has to be maintained by vendor specialists. But cases like this are unusual. I think some dirty laundry is going to get aired, too. It has long been rumored that the reason graphics card manufacturers are so stubborn in their secrecy is that they've all been committing massive intellectual-property theft on each other for decades. If this is true, it will be exposed, and the lawsuits will be entertaining. We're entering a new world, with a lot of ancient comfortable assumptions being blown up. It's going to be fun to watch. 2/2
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