All posts by Ross Anderson

Hacking the iPhone PIN retry counter

Academic papers, Hardware & signals, Legal issues, News coverage, Politics, Privacy technology, Security engineering

At our security group meeting on the 19th August, Sergei Skorobogatov demonstrated a NAND backup attack on an iPhone 5c. I typed in six wrong PINs and it locked; he removed the flash chip (which he’d desoldered and led out to a socket); he erased and restored the changed pages; he put it back in the phone; and I was able to enter a further six wrong PINs.

Sergei has today released a paper describing the attack.

During the recent fight between the FBI and Apple, FBI Director Jim Comey said this kind of attack wouldn’t work.

Yet another Android side channel: input stealing for fun and profit

Academic papers, Banking security, Cybercrime, Operating systems, Privacy technology, Usability

At PETS 2016 we presented a new side-channel attack in our paper Don’t Interrupt Me While I Type: Inferring Text Entered Through Gesture Typing on Android Keyboards. This was part of Laurent Simon‘s thesis, and won him the runner-up to the best student paper award.

We found that software on your smartphone can infer words you type in other apps by monitoring the aggregate number of context switches and the number of hardware interrupts. These are readable by permissionless apps within the virtual procfs filesystem (mounted under /proc). Three previous research groups had found that other files under procfs support side channels. But the files they used contained information about individual apps– e.g. the file /proc/uid_stat/victimapp/tcp_snd contains the number of bytes sent by “victimapp”. These files are no longer readable in the latest Android version.

We found that the “global” files – those that contain aggregate information about the system – also leak. So a curious app can monitor these global files as a user types on the phone and try to work out the words. We looked at smartphone keyboards that support “gesture typing”: a novel input mechanism democratized by SwiftKey, whereby a user drags their finger from letter to letter to enter words.

This work shows once again how difficult it is to prevent side channels: they come up in all sorts of interesting and unexpected ways. Fortunately, we think there is an easy fix: Google should simply disable access to all procfs files, rather than just the files that leak information about individual apps. Meanwhile, if you’re developing apps for privacy or anonymity, you should be aware that these risks exist.

Might Brexit make us more dishonest?

Academic papers, News coverage, Politics, Security psychology

When Lying Feels the Right Thing to Do reports three studies we did on what made people less or more likely to submit fraudulent insurance claims. Our first study found that people were more likely to cheat when rejected; the other two showed that rejected claimants were just as likely to cheat when this didn’t lead to financial gain, but that they felt more strongly when there was no money involved.

Our research was conducted as part of a broader research programme to investigate the deterrence of deception; our goal was to understand how to design better websites. However we can’t help wondering whether it might shine some light on the UK’s recent political turmoil. The Brexit campaigners were minorities of both main political parties and their anti-EU rhetoric had been rejected by the political mainstream for years; they had ideological rather than selfish motives. They ran a blatantly deceptive campaign, persisting in obvious untruths but abandoning them promptly after winning the vote. Rejection is not the only known factor in situational deception; it’s known, for example, that people with unmet goals are more likely to cheat than people who are simply doing their best, and that one bad apple can have a cascading effect. But it still makes you think.

The outcome and aftermath of the referendum have left many people feeling rejected, from remain voters through people who will lose financially to foreign residents of the UK. Our research shows that feelings of rejection can increase cheating by 15-30%; perhaps this might have measurable effects in some sectors. How one might disentangle this from the broader effects of diminished social solidarity, and from politicians simply setting a bad example, could be an interesting problems for social scientists.

Royal Society report on cybersecurity research

Academic papers, News coverage, Politics, Privacy technology, Security economics, Security engineering

The Royal Society has just published a report on cybersecurity research. I was a member of the steering group that tried to keep the policy team headed in the right direction. Its recommendation that governments preserve the robustness of encryption is welcome enough, given the new Russian law on access to crypto keys; it was nice to get, given the conservative nature of the Society. But I’m afraid the glass is only half full.

I was disappointed that the final report went along with the GCHQ line that security breaches should not be reported to affected data subjects, as in the USA, but to the agencies, as mandated in the EU’s NIS directive. Its call for an independent review of the UK’s cybersecurity needs may also achieve little. I was on John Beddington’s Blackett Review five years ago, and the outcome wasn’t published; it was mostly used to justify a budget increase for GCHQ. Its call for UK government work on standards is irrelevant post-Brexit; indeed standards made in Europe will probably be better without UK interference. Most of all, I cannot accept the report’s line that the government should help direct cybersecurity research. Most scientists agree that too much money already goes into directed programmes and not enough into responsive-mode and curiosity-driven research. In the case of security research there is a further factor: the stark conflict of interest between bona fide researchers, whose aim is that some of the people should enjoy some security and privacy some of the time, and agencies engaged in programmes such as Operation Bullrun whose goal is that this should not happen. GCHQ may want a “more responsive cybersecurity agenda”; but that’s the last thing people like me want them to have.

The report has in any case been overtaken by events. First, Brexit is already doing serious harm to research funding. Second, Brexit is also doing serious harm to the IT industry; we hear daily of listings posptoned, investments reconsidered and firms planning to move development teams and data overseas. Third, the Investigatory Powers bill currently before the House of Lords highlights the fact that surveillance debate in the West these days is more about access to data at rest and about whether the government can order firms to hack their customers.

While all three arms of the US government have drawn back on surveillance powers following the Snowden revelations, Theresa May has taken the hardest possible line. Her Investigatory Powers Bill will give her successors as Home Secretary sweeping powers to order firms in the UK to hand over data and help GCHQ hack their customers. Brexit will shield these powers from challenge in the European Court of Justice, making it much harder for a UK company to claim “adequacy” for its data protection arrangements in respect of EU data subjects. This will make it still less attractive for an IT company to keep in the UK either data that could be seized or engineering staff who could be coerced. I am seriously concerned that, together with Brexit, this will be the double whammy that persuades overseas firms not to invest in the UK, and that even causes some UK firms to leave. In the face of this massive self-harm, the measures suggested by the report are unlikely to help much.

Cambridge and Brexit

Politics, Security economics

If the UK leaves the European Union, it will cost Cambridge University about £100m, or about 10% of our turnover.

I present the details in an article today in the Cambridge News.

I reckon we will lose at least £60m of the £69m we get in European grants, at least £20m of our £237m fee income (most of which is from foreign students), at least £10m from Cambridge Assessment and Cambridge University Press, and £5m each from industry and charities. Although I’m an elected member of Council (the governing body) and the committee that sets the budget, all this comes from our published accounts.

And my estimates are conservative; the outcome could easily be worse, especially if foreign students desert us, or just can’t get visas after a popular vote against immigration.

Now everyone on Britain pays on average £4 a year to the EU and gets £2 back. The net contribution of £2 amounts to £12.5m for a town the size of Cambridge. The University alone is getting more than four times that back directly, and yet more indirectly. And the same goes for many other university towns too; even Newcastle gets more than would be raised by everyone in the city paying £2 a year.

But this is not just about money; it’s about who we are, and also about what other people perceive us to be. If Britain votes to leave Europe following a xenophobic campaign against immigrants, people overseas may conclude that Britain is to longer a cool place to study, or to start a research lab. Even some of the people already here will leave. We will do the best we can to keep the flame alight, but it will be very much harder for Cambridge to remain a world-leading university.

See also the Cambridge News editorial, and my piece yesterday on Brexit and tech.

The tech industry and Brexit

Politics, Security economics

The debate on whether Britain should leave the EU has largely ignored a factor of huge importance to the tech industry – network effects.

So I’ve written an article on what Brexit means for the tech industry from the viewpoint of information economics.

Network effects mean that the value of a transaction often depends on how many other people make similar transactions. They make our industry prone to monopolies. They ensure that the UK, with 1% of world population and 3% of GDP, has little influence on tech markets, which are mostly global. But the EU has real clout; Silicon Valley sees it as the world privacy regulator, as Washington doesn’t care and no-one else is big enough to matter. And most of the other regulations that IT people find annoying, from IP laws to export controls, are also embedded in international treaties. We can’t just tear up the annoying “red tape”, as the Brexit crowd suggest.

Brexit would not only diminish our influence on the laws that affect tech – many of which reflect negative network effects. It would make startups more expensive, so UK firms would have a harder time exploiting the positive network effects that are often the key to success. And it would damage the successful tech clusters we do have in Cambridge and in London.

Tech clusters need a number of things to thrive; and it’s not just technical network effects that matter, but labour-market network effects too. And there’s quite a lot of research on that. As good engineers can earn good money and live wherever we want, we congregate in places that are good places to live. They are always open and liberal places, where it’s fine to be from an ethnic minority, or an immigrant, or gay. What would the world’s best and brightest engineers think about moving to Britain if we vote for xenophobia on Thursday?

The article is in Computer Weekly, and there’s also a pdf here.

GCHQ helps banks dump fraud losses on customers

Authentication, Banking security, Cybercrime, Legal issues, News coverage, Politics, Security economics, Security psychology

We recently reported that the Commissioner of the Met, Sir Bernard Hogan-Howe, said that banks should not refund fraud victims as this would just make people careless with their passwords and antivirus. The banks’ desire to blame fraud victims if they can, to avoid refunding them, is rational enough, but for a police chief to support them was disgraceful. Thirty years ago, a chief constable might have said that rape victims had themselves to blame for wearing nice clothes; if he were to say that nowadays, he’d be sacked. Hogan-Howe’s view of bank fraud is just as uninformed, and just as offensive to victims.

Our spooky friends at Cheltenham have joined the party. The Register reports a story in the Financial Times (behind a paywall) which says GCHQ believes that “companies must do more to try and encourage their customers to improve their cyber security standards. Customers using outdated software – sometimes riddled with vulnerabilities that hackers can exploit – are a weak link in the UK’s cyber defences.” There is no mention of the banks’ own outdated technology, or of GCHQ’s role in keeping consumer software vulnerable.

The elegant scribblers at the Financial Times are under the impression that “At present, banks routinely cover the cost of fraud, regardless of blame.” So they clearly are not regular readers of Light Blue Touchpaper.

The spooks are slightly more cautious; according to the FT, GCHQ “has told the private sector it will not take responsibility for regulatory failings”. I’m sure the banks will heave a big sigh of relief that their cosy relationship with the police, the ombudsman and the FCA will not be disturbed.

We will have to change our security-economics teaching material so we don’t just talk about the case where “Alice guards a system and Bob pays the costs of failure”, but also this new case where “Alice guards a system, and bribes the government to compel Bob to pay the costs of failure.” Now we know how Hogan-Howe is paid off; the banks pay for his Dedicated Card and Payment Crime Unit. But how are they paying off GCHQ, and what else are they getting as part of the deal?