Entries Tagged "artificial intelligence"
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Ben Buchanan has written “A National Security Research Agenda for Cybersecurity and Artificial Intelligence.” It’s really good — well worth reading.
MIT researchers have built a system that fools natural-language processing systems by swapping words with synonyms:
The software, developed by a team at MIT, looks for the words in a sentence that are most important to an NLP classifier and replaces them with a synonym that a human would find natural. For example, changing the sentence “The characters, cast in impossibly contrived situations, are totally estranged from reality” to “The characters, cast in impossibly engineered circumstances, are fully estranged from reality” makes no real difference to how we read it. But the tweaks made an AI interpret the sentences completely differently.
The results of this adversarial machine learning attack are impressive:
For example, Google’s powerful BERT neural net was worse by a factor of five to seven at identifying whether reviews on Yelp were positive or negative.
Abstract: Machine learning algorithms are often vulnerable to adversarial examples that have imperceptible alterations from the original counterparts but can fool the state-of-the-art models. It is helpful to evaluate or even improve the robustness of these models by exposing the maliciously crafted adversarial examples. In this paper, we present TextFooler, a simple but strong baseline to generate natural adversarial text. By applying it to two fundamental natural language tasks, text classification and textual entailment, we successfully attacked three target models, including the powerful pre-trained BERT, and the widely used convolutional and recurrent neural networks. We demonstrate the advantages of this framework in three ways: (1) effective — it outperforms state-of-the-art attacks in terms of success rate and perturbation rate, (2) utility-preserving — it preserves semantic content and grammaticality, and remains correctly classified by humans, and (3) efficient — it generates adversarial text with computational complexity linear to the text length.
EDITED TO ADD: This post has been translated into Spanish.
Microsoft is training a machine-learning system to find software bugs:
At Microsoft, 47,000 developers generate nearly 30 thousand bugs a month. These items get stored across over 100 AzureDevOps and GitHub repositories. To better label and prioritize bugs at that scale, we couldn’t just apply more people to the problem. However, large volumes of semi-curated data are perfect for machine learning. Since 2001 Microsoft has collected 13 million work items and bugs. We used that data to develop a process and machine learning model that correctly distinguishes between security and non-security bugs 99 percent of the time and accurately identifies the critical, high priority security bugs, 97 percent of the time.
I wrote about this in 2018:
The problem of finding software vulnerabilities seems well-suited for ML systems. Going through code line by line is just the sort of tedious problem that computers excel at, if we can only teach them what a vulnerability looks like. There are challenges with that, of course, but there is already a healthy amount of academic literature on the topic — and research is continuing. There’s every reason to expect ML systems to get better at this as time goes on, and some reason to expect them to eventually become very good at it.
Finding vulnerabilities can benefit both attackers and defenders, but it’s not a fair fight. When an attacker’s ML system finds a vulnerability in software, the attacker can use it to compromise systems. When a defender’s ML system finds the same vulnerability, he or she can try to patch the system or program network defenses to watch for and block code that tries to exploit it.
But when the same system is in the hands of a software developer who uses it to find the vulnerability before the software is ever released, the developer fixes it so it can never be used in the first place. The ML system will probably be part of his or her software design tools and will automatically find and fix vulnerabilities while the code is still in development.
Fast-forward a decade or so into the future. We might say to each other, “Remember those years when software vulnerabilities were a thing, before ML vulnerability finders were built into every compiler and fixed them before the software was ever released? Wow, those were crazy years.” Not only is this future possible, but I would bet on it.
Getting from here to there will be a dangerous ride, though. Those vulnerability finders will first be unleashed on existing software, giving attackers hundreds if not thousands of vulnerabilities to exploit in real-world attacks. Sure, defenders can use the same systems, but many of today’s Internet of Things (IoT) systems have no engineering teams to write patches and no ability to download and install patches. The result will be hundreds of vulnerabilities that attackers can find and use.
The New York Times has a long story about Clearview AI, a small company that scrapes identified photos of people from pretty much everywhere, and then uses unstated magical AI technology to identify people in other photos.
His tiny company, Clearview AI, devised a groundbreaking facial recognition app. You take a picture of a person, upload it and get to see public photos of that person, along with links to where those photos appeared. The system — whose backbone is a database of more than three billion images that Clearview claims to have scraped from Facebook, YouTube, Venmo and millions of other websites — goes far beyond anything ever constructed by the United States government or Silicon Valley giants.
Federal and state law enforcement officers said that while they had only limited knowledge of how Clearview works and who is behind it, they had used its app to help solve shoplifting, identity theft, credit card fraud, murder and child sexual exploitation cases.
But without public scrutiny, more than 600 law enforcement agencies have started using Clearview in the past year, according to the company, which declined to provide a list. The computer code underlying its app, analyzed by The New York Times, includes programming language to pair it with augmented-reality glasses; users would potentially be able to identify every person they saw. The tool could identify activists at a protest or an attractive stranger on the subway, revealing not just their names but where they lived, what they did and whom they knew.
And it’s not just law enforcement: Clearview has also licensed the app to at least a handful of companies for security purposes.
EDITED TO ADD (1/23): Twitter told the company to stop scraping its photos.
Presidential campaign season is officially, officially, upon us now, which means it’s time to confront the weird and insidious ways in which technology is warping politics. One of the biggest threats on the horizon: artificial personas are coming, and they’re poised to take over political debate. The risk arises from two separate threads coming together: artificial intelligence-driven text generation and social media chatbots. These computer-generated “people” will drown out actual human discussions on the Internet.
Text-generation software is already good enough to fool most people most of the time. It’s writing news stories, particularly in sports and finance. It’s talking with customers on merchant websites. It’s writing convincing op-eds on topics in the news (though there are limitations). And it’s being used to bulk up “pink-slime journalism” — websites meant to appear like legitimate local news outlets but that publish propaganda instead.
There’s a record of algorithmic content pretending to be from individuals, as well. In 2017, the Federal Communications Commission had an online public-commenting period for its plans to repeal net neutrality. A staggering 22 million comments were received. Many of them — maybe half — were fake, using stolen identities. These comments were also crude; 1.3 million were generated from the same template, with some words altered to make them appear unique. They didn’t stand up to even cursory scrutiny.
These efforts will only get more sophisticated. In a recent experiment, Harvard senior Max Weiss used a text-generation program to create 1,000 comments in response to a government call on a Medicaid issue. These comments were all unique, and sounded like real people advocating for a specific policy position. They fooled the Medicaid.gov administrators, who accepted them as genuine concerns from actual human beings. This being research, Weiss subsequently identified the comments and asked for them to be removed, so that no actual policy debate would be unfairly biased. The next group to try this won’t be so honorable.
Chatbots have been skewing social-media discussions for years. About a fifth of all tweets about the 2016 presidential election were published by bots, according to one estimate, as were about a third of all tweets about that year’s Brexit vote. An Oxford Internet Institute report from last year found evidence of bots being used to spread propaganda in 50 countries. These tended to be simple programs mindlessly repeating slogans: a quarter million pro-Saudi “We all have trust in Mohammed bin Salman” tweets following the 2018 murder of Jamal Khashoggi, for example. Detecting many bots with a few followers each is harder than detecting a few bots with lots of followers. And measuring the effectiveness of these bots is difficult. The best analyses indicate that they did not affect the 2016 US presidential election. More likely, they distort people’s sense of public sentiment and their faith in reasoned political debate. We are all in the middle of a novel social experiment.
Over the years, algorithmic bots have evolved to have personas. They have fake names, fake bios, and fake photos — sometimes generated by AI. Instead of endlessly spewing propaganda, they post only occasionally. Researchers can detect that these are bots and not people, based on their patterns of posting, but the bot technology is getting better all the time, outpacing tracking attempts. Future groups won’t be so easily identified. They’ll embed themselves in human social groups better. Their propaganda will be subtle, and interwoven in tweets about topics relevant to those social groups.
Combine these two trends and you have the recipe for nonhuman chatter to overwhelm actual political speech.
Soon, AI-driven personas will be able to write personalized letters to newspapers and elected officials, submit individual comments to public rule-making processes, and intelligently debate political issues on social media. They will be able to comment on social-media posts, news sites, and elsewhere, creating persistent personas that seem real even to someone scrutinizing them. They will be able to pose as individuals on social media and send personalized texts. They will be replicated in the millions and engage on the issues around the clock, sending billions of messages, long and short. Putting all this together, they’ll be able to drown out any actual debate on the Internet. Not just on social media, but everywhere there’s commentary.
Maybe these persona bots will be controlled by foreign actors. Maybe it’ll be domestic political groups. Maybe it’ll be the candidates themselves. Most likely, it’ll be everybody. The most important lesson from the 2016 election about misinformation isn’t that misinformation occurred; it is how cheap and easy misinforming people was. Future technological improvements will make it all even more affordable.
Our future will consist of boisterous political debate, mostly bots arguing with other bots. This is not what we think of when we laud the marketplace of ideas, or any democratic political process. Democracy requires two things to function properly: information and agency. Artificial personas can starve people of both.
Solutions are hard to imagine. We can regulate the use of bots — a proposed California law would require bots to identify themselves — but that is effective only against legitimate influence campaigns, such as advertising. Surreptitious influence operations will be much harder to detect. The most obvious defense is to develop and standardize better authentication methods. If social networks verify that an actual person is behind each account, then they can better weed out fake personas. But fake accounts are already regularly created for real people without their knowledge or consent, and anonymous speech is essential for robust political debate, especially when speakers are from disadvantaged or marginalized communities. We don’t have an authentication system that both protects privacy and scales to the billions of users.
We can hope that our ability to identify artificial personas keeps up with our ability to disguise them. If the arms race between deep fakes and deep-fake detectors is any guide, that’ll be hard as well. The technologies of obfuscation always seem one step ahead of the technologies of detection. And artificial personas will be designed to act exactly like real people.
In the end, any solutions have to be nontechnical. We have to recognize the limitations of online political conversation, and again prioritize face-to-face interactions. These are harder to automate, and we know the people we’re talking with are actual people. This would be a cultural shift away from the internet and text, stepping back from social media and comment threads. Today that seems like a completely unrealistic solution.
Misinformation efforts are now common around the globe, conducted in more than 70 countries. This is the normal way to push propaganda in countries with authoritarian leanings, and it’s becoming the way to run a political campaign, for either a candidate or an issue.
Artificial personas are the future of propaganda. And while they may not be effective in tilting debate to one side or another, they easily drown out debate entirely. We don’t know the effect of that noise on democracy, only that it’ll be pernicious, and that it’s inevitable.
This essay previously appeared in TheAtlantic.com.
EDITED TO ADD: Jamie Susskind wrote a similar essay.
EDITED TO ADD (3/16): This essay has been translated into Spanish.
EDITED TO ADD (6/4): This essay has been translated into Portuguese.
This seems to be an identity theft first:
Criminals used artificial intelligence-based software to impersonate a chief executive’s voice and demand a fraudulent transfer of €220,000 ($243,000) in March in what cybercrime experts described as an unusual case of artificial intelligence being used in hacking.
Another news article.
Voice systems are increasingly using AI techniques to determine emotion. A new paper describes an AI-based countermeasure to mask emotion in spoken words.
Their method for masking emotion involves collecting speech, analyzing it, and extracting emotional features from the raw signal. Next, an AI program trains on this signal and replaces the emotional indicators in speech, flattening them. Finally, a voice synthesizer re-generates the normalized speech using the AIs outputs, which gets sent to the cloud. The researchers say that this method reduced emotional identification by 96 percent in an experiment, although speech recognition accuracy decreased, with a word error rate of 35 percent.
Yesterday, I blogged about a Facebook plan to backdoor WhatsApp by adding client-side scanning and filtering. It seems that I was wrong, and there are no such plans.
Leetaru extrapolated a lot out of very little. I watched the video (the relevant section is at the 23:00 mark), and it doesn’t talk about client-side scanning of messages. It doesn’t talk about messaging apps at all. It discusses using AI techniques to find bad content on Facebook, and the difficulties that arise from dynamic content:
So far, we have been keeping this fight [against bad actors and harmful content] on familiar grounds. And that is, we have been training our AI models on the server and making inferences on the server when all the data are flooding into our data centers.
While this works for most scenarios, it is not the ideal setup for some unique integrity challenges. URL masking is one such problem which is very hard to do. We have the traditional way of server-side inference. What is URL masking? Let us imagine that a user sees a link on the app and decides to click on it. When they click on it, Facebook actually logs the URL to crawl it at a later date. But…the publisher can dynamically change the content of the webpage to make it look more legitimate [to Facebook]. But then our users click on the same link, they see something completely different — oftentimes it is disturbing; oftentimes it violates our policy standards. Of course, this creates a bad experience for our community that we would like to avoid. This and similar integrity problems are best solved with AI on the device.
That might be true, but it also would hand whatever secret-AI sauce Facebook has to every one of its users to reverse engineer — which means it’s probably not going to happen. And it is a dumb idea, for reasons Steve Bellovin has pointed out.
Facebook’s first published response was a comment on the Hacker News website from a user named “wcathcart,” which Cardozo assures me is Will Cathcart, the vice president of WhatsApp. (I have no reason to doubt his identity, but surely there is a more official news channel that Facebook could have chosen to use if they wanted to.) Cathcart wrote:
We haven’t added a backdoor to WhatsApp. The Forbes contributor referred to a technical talk about client side AI in general to conclude that we might do client side scanning of content on WhatsApp for anti-abuse purposes.
To be crystal clear, we have not done this, have zero plans to do so, and if we ever did it would be quite obvious and detectable that we had done it. We understand the serious concerns this type of approach would raise which is why we are opposed to it.
Facebook’s second published response was a comment on my original blog post, which has been confirmed to me by the WhatsApp people as authentic. It’s more of the same.
So, this was a false alarm. And, to be fair, Alec Muffet called foul on the first Forbes piece:
So, here’s my pre-emptive finger wag: Civil Society’s pack mentality can make us our own worst enemies. If we go around repeating one man’s Germanic conspiracy theory, we may doom ourselves to precisely what we fear. Instead, we should we must take steps to constructively demand what we actually want: End to End Encryption which is worthy of the name.
Blame accepted. But in general, this is the sort of thing we need to watch for. End-to-end encryption only secures data in transit. The data has to be in the clear on the device where it is created, and it has to be in the clear on the device where it is consumed. Those are the obvious places for an eavesdropper to get a copy.
Final note: If they want to be trusted, Adam Shostack and I gave them a road map.
Hacker News thread.
EDITED TO ADD (8/4): Slashdot covered my retraction.
According to foreign policy experts and the defense establishment, the United States is caught in an artificial intelligence arms race with China — one with serious implications for national security. The conventional version of this story suggests that the United States is at a disadvantage because of self-imposed restraints on the collection of data and the privacy of its citizens, while China, an unrestrained surveillance state, is at an advantage. In this vision, the data that China collects will be fed into its systems, leading to more powerful AI with capabilities we can only imagine today. Since Western countries can’t or won’t reap such a comprehensive harvest of data from their citizens, China will win the AI arms race and dominate the next century.
This idea makes for a compelling narrative, especially for those trying to justify surveillance — whether government- or corporate-run. But it ignores some fundamental realities about how AI works and how AI research is conducted.
Thanks to advances in machine learning, AI has flipped from theoretical to practical in recent years, and successes dominate public understanding of how it works. Machine learning systems can now diagnose pneumonia from X-rays, play the games of go and poker, and read human lips, all better than humans. They’re increasingly watching surveillance video. They are at the core of self-driving car technology and are playing roles in both intelligence-gathering and military operations. These systems monitor our networks to detect intrusions and look for spam and malware in our email.
And it’s true that there are differences in the way each country collects data. The United States pioneered “surveillance capitalism,” to use the Harvard University professor Shoshana Zuboff’s term, where data about the population is collected by hundreds of large and small companies for corporate advantage — and mutually shared or sold for profit The state picks up on that data, in cases such as the Centers for Disease Control and Prevention’s use of Google search data to map epidemics and evidence shared by alleged criminals on Facebook, but it isn’t the primary user.
China, on the other hand, is far more centralized. Internet companies collect the same sort of data, but it is shared with the government, combined with government-collected data, and used for social control. Every Chinese citizen has a national ID number that is demanded by most services and allows data to easily be tied together. In the western region of Xinjiang, ubiquitous surveillance is used to oppress the Uighur ethnic minority — although at this point there is still a lot of human labor making it all work. Everyone expects that this is a test bed for the entire country.
Data is increasingly becoming a part of control for the Chinese government. While many of these plans are aspirational at the moment — there isn’t, as some have claimed, a single “social credit score,” but instead future plans to link up a wide variety of systems — data collection is universally pushed as essential to the future of Chinese AI. One executive at search firm Baidu predicted that the country’s connected population will provide them with the raw data necessary to become the world’s preeminent tech power. China’s official goal is to become the world AI leader by 2030, aided in part by all of this massive data collection and correlation.
This all sounds impressive, but turning massive databases into AI capabilities doesn’t match technological reality. Current machine learning techniques aren’t all that sophisticated. All modern AI systems follow the same basic methods. Using lots of computing power, different machine learning models are tried, altered, and tried again. These systems use a large amount of data (the training set) and an evaluation function to distinguish between those models and variations that work well and those that work less well. After trying a lot of models and variations, the system picks the one that works best. This iterative improvement continues even after the system has been fielded and is in use.
So, for example, a deep learning system trying to do facial recognition will have multiple layers (hence the notion of “deep”) trying to do different parts of the facial recognition task. One layer will try to find features in the raw data of a picture that will help find a face, such as changes in color that will indicate an edge. The next layer might try to combine these lower layers into features like shapes, looking for round shapes inside of ovals that indicate eyes on a face. The different layers will try different features and will be compared by the evaluation function until the one that is able to give the best results is found, in a process that is only slightly more refined than trial and error.
Large data sets are essential to making this work, but that doesn’t mean that more data is automatically better or that the system with the most data is automatically the best system. Train a facial recognition algorithm on a set that contains only faces of white men, and the algorithm will have trouble with any other kind of face. Use an evaluation function that is based on historical decisions, and any past bias is learned by the algorithm. For example, mortgage loan algorithms trained on historic decisions of human loan officers have been found to implement redlining. Similarly, hiring algorithms trained on historical data manifest the same sexism as human staff often have. Scientists are constantly learning about how to train machine learning systems, and while throwing a large amount of data and computing power at the problem can work, more subtle techniques are often more successful. All data isn’t created equal, and for effective machine learning, data has to be both relevant and diverse in the right ways.
Future research advances in machine learning are focused on two areas. The first is in enhancing how these systems distinguish between variations of an algorithm. As different versions of an algorithm are run over the training data, there needs to be some way of deciding which version is “better.” These evaluation functions need to balance the recognition of an improvement with not over-fitting to the particular training data. Getting functions that can automatically and accurately distinguish between two algorithms based on minor differences in the outputs is an art form that no amount of data can improve.
The second is in the machine learning algorithms themselves. While much of machine learning depends on trying different variations of an algorithm on large amounts of data to see which is most successful, the initial formulation of the algorithm is still vitally important. The way the algorithms interact, the types of variations attempted, and the mechanisms used to test and redirect the algorithms are all areas of active research. (An overview of some of this work can be found here; even trying to limit the research to 20 papers oversimplifies the work being done in the field.) None of these problems can be solved by throwing more data at the problem.
The British AI company DeepMind’s success in teaching a computer to play the Chinese board game go is illustrative. Its AlphaGo computer program became a grandmaster in two steps. First, it was fed some enormous number of human-played games. Then, the game played itself an enormous number of times, improving its own play along the way. In 2016, AlphaGo beat the grandmaster Lee Sedol four games to one.
While the training data in this case, the human-played games, was valuable, even more important was the machine learning algorithm used and the function that evaluated the relative merits of different game positions. Just one year later, DeepMind was back with a follow-on system: AlphaZero. This go-playing computer dispensed entirely with the human-played games and just learned by playing against itself over and over again. It plays like an alien. (It also became a grandmaster in chess and shogi.)
These are abstract games, so it makes sense that a more abstract training process works well. But even something as visceral as facial recognition needs more than just a huge database of identified faces in order to work successfully. It needs the ability to separate a face from the background in a two-dimensional photo or video and to recognize the same face in spite of changes in angle, lighting, or shadows. Just adding more data may help, but not nearly as much as added research into what to do with the data once we have it.
Meanwhile, foreign-policy and defense experts are talking about AI as if it were the next nuclear arms race, with the country that figures it out best or first becoming the dominant superpower for the next century. But that didn’t happen with nuclear weapons, despite research only being conducted by governments and in secret. It certainly won’t happen with AI, no matter how much data different nations or companies scoop up.
It is true that China is investing a lot of money into artificial intelligence research: The Chinese government believes this will allow it to leapfrog other countries (and companies in those countries) and become a major force in this new and transformative area of computing — and it may be right. On the other hand, much of this seems to be a wasteful boondoggle. Slapping “AI” on pretty much anything is how to get funding. The Chinese Ministry of Education, for instance, promises to produce “50 world-class AI textbooks,” with no explanation of what that means.
In the democratic world, the government is neither the leading researcher nor the leading consumer of AI technologies. AI research is much more decentralized and academic, and it is conducted primarily in the public eye. Research teams keep their training data and models proprietary but freely publish their machine learning algorithms. If you wanted to work on machine learning right now, you could download Microsoft’s Cognitive Toolkit, Google’s Tensorflow, or Facebook’s Pytorch. These aren’t toy systems; these are the state-of-the art machine learning platforms.
AI is not analogous to the big science projects of the previous century that brought us the atom bomb and the moon landing. AI is a science that can be conducted by many different groups with a variety of different resources, making it closer to computer design than the space race or nuclear competition. It doesn’t take a massive government-funded lab for AI research, nor the secrecy of the Manhattan Project. The research conducted in the open science literature will trump research done in secret because of the benefits of collaboration and the free exchange of ideas.
While the United States should certainly increase funding for AI research, it should continue to treat it as an open scientific endeavor. Surveillance is not justified by the needs of machine learning, and real progress in AI doesn’t need it.
Sidebar photo of Bruce Schneier by Joe MacInnis.