I’m at the twenty-fifth Security Protocols Workshop, of which the theme is protocols with multiple objectives. I’ll try to liveblog the talks in followups to this post.
The following is an op-ed I wrote in today’s Times. It appeared in their Thunderer column.
You’re less likely to be treated fairly by your bank if you’re elderly, poor, female or black. We’ve suspected this for years, and finally The Times has dug up the numbers to prove it.
Fraud victims who’re refused compensation often contact our security research group at Cambridge after they find we work on payment fraud. We call this stream of complaints our ‘fraud telescope’ as it gives us early warning of what the bad guys are up to. We’ve had more than 2,000 cases over 25 years.
In recent years we’ve started to realise what we weren’t seeing. The “dark matter” in the fraud universe is the missing victims: we don’t see that many middle-class white men. The victims who do come to us are disproportionately elderly, poor, female, or black. But crime surveys tell us that the middle classes and the young are more likely to be victims of fraud, so it’s hard to avoid the conclusion that banks are less generous to some of their customers.
We raised the issue of discrimination in 2011 with one of the banks and with the Commission for Racial Equality, but as no-one was keeping records, nothing could be proved, until today.
How can this discrimination happen? Well, UK rules give banks a lot of discretion to decide whether to refund a victim, and the first responders often don’t know the full story. If your HSBC card was compromised by a skimmer on a Tesco ATM, there’s no guarantee that Tesco will have told anyone (unlike in America, where the law forces Tesco to tell you). And the fraud pattern might be something entirely new. So bank staff end up making judgement calls like “Is this customer telling the truth?” and “How much is their business worth to us?” This in turn sets the stage for biases and prejudices to kick in, however subconsciously. Add management pressure to cut costs, sometimes even bonuses for cutting them, and here we are.
There are two lessons. First, banks need to train staff to be aware of unconscious bias (as universities do), and monitor their performance.
Second, the Financial Conduct Authority needs to protect all customers properly. It seems to be moving in the right direction; after the recent fraud against tens of thousands of Tesco Bank account holders, it said it expected fraud victims to be made good immediately. This has been the law in the USA since the 1980s and it must become a firm rule here too.
2016 might not have been the best of years, so instead of doing a Christmas card I’ve written a magical fantasy story instead.
A happy Christmas to all, and here’s hoping we have a better 2017.
Now that everyone’s distracted with the supreme court case on Brexit, you can expect the government to sneak out something it’s ashamed of. Health secretary Jeremy Hunt has decided to ignore the wishes of over a million people who opted out of having their hospital records given to third parties such as drug companies, and the ICO has decided to pretend that the anonymisation mechanisms he says he’ll use instead are sufficient. One gently smoking gun is the fifth bullet in a new webpage here, where the Department of Health claims that when it says the data are anonymous, your wishes will be ignored. The news has been broken in an article in the Health Services Journal (it’s behind a paywall, as a splendid example of transparency) with the Wellcome Trust praising the ICO’s decision not to take action against the Department. We are assured that “the data is seen as crucial for vital research projects”. The exchange of letters with privacy campaigners that led up to this decision can be found here, here, here, here, here, here, and here.
An early portent of this u-turn was reported here in 2014 when officials reckoned that the only way they could still do administrative tasks such as calculating doctors’ bonuses was to just pretend that the data are anonymous even though they know it isn’t really. Then, after the care.data scandal showed that a billion records had been sold to over a thousand purchasers, we reported here how HES data had also been sold and how the minister seemed to have misled parliament about this.
I will be talking about ethics of all this on Thursday. Even if ministers claim that stolen medical records are OK to use, researchers must not act as if this is true; if patients end up trusting doctors as little as we trust politicians, then medical research will be in serious trouble. There is a video of a previous version of this talk here.
Meanwhile, if you’re annoyed that Jeremy Hunt proposes to ignore not just your privacy rights but your express wishes, you can send him a notice under Section 10 of the Data Protection Act forbidding him from disclosing your data. The Department has complied with such notices in the past, albeit with bad grace as they have no automated way to do it. If thousands of people serve such notices, they may finally have to stand up to the drug company lobbyists and write the missing software. For more, see here.
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.
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?
A manuscript authored by myself and Richard Clayton has recently been published as an advance access paper in the criminology journal Deviant Behavior.
This research uses criminological theories to study those who operate ‘booter services’: websites that illegally offer denial of service attacks for a fee. We interviewed those operating the sites, and found that booter services provide ‘easy money’ for the young males that run them. The operators claim they provide legitimate services for network testing, despite acknowledging that their services are used to attack other targets. Booter services are advertised through the online communities where the skills are learned and definitions favorable toward offending are shared. Some financial services proactively frustrate the provision of booter services, by closing the accounts used for receiving payments.
Commissioner Hogan-Howe of the Met said on Thursday that the banks should not refund fraud victims because it “rewards” them for being lax about internet security. This was too much to pass up, so I wrote a letter to the editor of the Times, which has just been published. As the Times is behind a paywall, here is the text.
Sir, Sir Bernard Hogan-Howe argues that banks should not refund online fraud victims as this would make people careless with their passwords and anti-virus software (p1, March 24, and letters Mar 25 & 26). This is called secondary victimisation. 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.
About 5 percent of computers running Windows are infected with malware, and common bank fraud malware such as Zeus lets the fraudster redirect transactions. You think you’re paying £150 to your electricity bill, while the malware is actually sending £9000 to Russia. The average person is helpless against this; everything seems normal, and antivirus products usually only detect it afterwards.
Much of the blame lies with the banks, who let the users of potentially infected computers make large payments instantly, rather than after a day or two, as used to be the case. They take this risk because regulators let them dump much of the cost of the resulting fraud on customers.
The elephant in the room is that the Met has been claiming for years that property crime is falling, when in fact it’s just going online like everything else. We’re now starting to get better crime figures; it’s time we got better policing, and better bank regulation too.
Ross Anderson FRS FREng
Professor of Security Engineering
University of Cambridge
I will be trying to liveblog Financial Cryptography 2016, which is the twentieth anniversary of the conference. The opening keynote was by David Chaum, who invented digital cash over thirty years ago. From then until the first FC people believed that cryptography could enable commerce and also protect privacy; since then pessimism has slowly set in, and sometimes it seems that although we’re still fighting tactical battles, we’ve lost the war. Since Snowden people have little faith in online privacy, and now we see Tim Cook in a position to decide which seventy phones to open. Is there a way to fight back against a global adversary whose policy is “full take”, and where traffic data can be taken with no legal restraint whatsoever? That is now the threat model for designers of anonymity systems. He argues that in addition to a large anonymity set, a future social media system will need a fixed set of servers in order to keep end-to-end latency within what chat users expect. As with DNS we should have servers operated by (say ten) different principals; unlike in that case we don’t want to have most of the independent parties financed by the US government. The root servers could be implemented as unattended seismic observatories, as reported by Simmons in the arms control context; such devices are fairly easy to tamper-proof.
The crypto problem is how to do multi-jurisdiction message processing that protects not just content but also metadata. Systems like Tor cost latency, while multi-party computation costs a lot of cycles. His new design, PrivaTegrity, takes low-latency crypto building blocks then layers on top of them transaction protocols with large anonymity sets. The key component is c-Mix, whose spec up as an eprint here. There’s a precomputation using homomorphic encryption to set up paths and keys; in real-time operations each participating phone has a shared secret with each mix server so things can run at chat speed. A PrivaTegrity message is four c-Mix batches that use the same permutation. Message models supported include not just chat but publishing short anonymous messages, providing an untraceable return address so people can contact you anonymously, group chat, and limiting sybils by preventing more than one pseudonym being used. (There are enduring pseudonyms with valuable credentials.) It can handle large payloads using private information retrieval, and also do pseudonymous digital transactions with a latency of two seconds rather than the hour or so that bitcoin takes. The anonymous payment system has the property that the payer has proof of what he paid to whom, while the recipient has no proof of who paid him; that’s exactly what corrupt officials, money launderers and the like don’t want, but exactly what we do want from the viewpoint of consumer protection. He sees PrivaTegrity as the foundation of a “polyculture” of secure computing from multiple vendors that could be outside the control of governments once more. In questions, Adi Shamir questioned whether such an ecosystem was consistent with the reality of pervasive software vulnerabilities, regardless of the strength of the cryptography.
I will try to liveblog later sessions as followups to this post.