A bug has been found and fixed in the FreeBSD kernel that would allow someone with malicious intent to crash a running system. It’d be difficult to achieve unless the attacker had console access. However it’s been patched for all supported systems. See here for all the details (which I won’t repeat).
The sysarch() system call is used to get/set processor-specific stuff. You’re not supposed to call it directly; you’re supposed to call a processor-specific library if you want to do things like that, but you still can call it if you want to. On processors that support memory segments, such as i386, there is a Local Descriptor Table (LDT) to manage them if you want to mess with specific stuff like that. However, for security reasons, you can only modify the LDT using the sysarch() call, which checks what you’re trying to do and prevents applications from doing anything crazy.
Unfortunately the AMD64 implementation of the code gets the checking wrong. If you use a signed integer it’s always going to be less than another unsigned value, and when it compares the two parameters to make sure that one is less than the other it passes when it shouldn’t, and the rogue parameter causes it to go funky-deux and overwrite a shed load of stuff.
This is in all in:
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Mid-Post
/sys/amd64/amd64/sys_machdep.c
in the function:
int amd64_set_ldt(td, uap, descs)
The FreeBSD advisory contains a patch for all “supported” versions; but what if you’re using an older one? Using the information from Core it’s easy enough to patch. But what else is affected?
To save you the trouble, I’ve looked back at earlier versions. The problem code definitely exists in the AMD64 versions for 8.x, but isn’t present in any 7.x, as far as I can tell. The system call simply doesn’t exist. On i386 versions, I can’t see any obvious problem with the code.
How worried should we be? If someone breaks in to a system with shell access, they will be able to crash it. However, I think it’s very unlikely that any service is written in such a way that malicious data could cause the necessary parameters to be sent to sysarch() call. In fact, on checking the ports collection, it’s not exactly used all over the place. You’re highly unlikely to be running any application that even makes the call.
There’s a bug in all by the most recent versions of the Android operating system that can theoretically allow attackers to take over the device simply by viewing a web page or downloading a media file. It’s actually in the Stagefright library, and was the talk of Black Hat last August. Then it was considered hard to exploit, but security researcher Hanan Be’er at North-Bit in Israel has now published a paper proving it’s very dangerous.
Stagefright is the name of the media processing library found in all versions of Android you’re likely to find. It opens and reads any media downloaded to the device. With a specially crafted file you can cause it to crash when it does this; you don’t have to even play the file. However, it has been difficult to make use of this fact to “break out” and do anything more nasty.
Since Android 5.0, a system called Address Space Layout Randomisation (ASLR) has been in use. Basically the memory space is shuffled randomly so malicious code doesn’t know where anything else is, making attacks more difficult. This made exploiting Stagefright’s flaws a lot harder. The fact that the problem exists on Android 2.2 to 4.x, which doesn’t do ASLR, has been the subject of much complacency. Google has released fixes for the bug, known as CVE-2015-3864, but by no means have all the Android devices been updated. I guess that the vast majority have not, including the recent ones using Android 5.x. The infrastructure for updating Android simply doesn’t exist. Apple’s devices are very exploitable, but at least they have a mechanism for updating them.
So how does the North-Bit exploit work? It’s actually very straightforward. First you deliver a dodgy video file to the device; putting it on a web site is the obvious, easy method. This will cause Stagefright to crash and restart in a known state. When it does this, some JavaScript running on the same page slurps various parameters on the system, such as the current location of libc, and sends it back to the attacker. A new video file is then created and sent using this information, and it’s game over – possibly after a few tries, but North-Bit says the exploit is reliable.
How worried should we be? I’d say we should be very worried. Unless your device manufacturer and/or mobile network rolls out the patch, I can’t see any mitigation.
Tim Cook – time he was sent to jail?You can’t have missed the furore over Apple’s refusal to help the CIA get the data from a terrorist murderers iPhone. On the one side the CIA says that we need the data to protect the public, a line with the judiciary of the USA agrees with, and Apple should do everything possible to get it for them. On the other side there’s Apple’s PR engine trying (successfully) to spin the story and avoid complying with the court order.
In the mean time the Brazilians haven’t shown such deference to a cultural icon when it comes to Facebook owned WhatsApp refusing to hand over data concerning a major drugs trafficker, even after several court orders. The Brazilian authorities have arrested Diego Dzodan, Facebook’s hancho in Latin America, and thrown him in jail until such time as the company obeys the law.
Perhaps he Americans could try that with Tim Cook – you break the law, you go to jail.
Meanwhile, Apple might seem to be setting itself up as the criminals friend over this. In the land of the free where profit is king, I guess their money is as good as anyone else’s so perhaps we should be too judgemental. But in an outrageous spin, Apple has told the world that if they comply with the court order then all Apple handsets will have a backdoor and no longer be secure. This is disingenuous. The situation is this:
Apple encrypts the data stored on the phone. You have to enter a password to unlock it. If you enter ten wrong passwords it will wipe the data from the phone. The CIA has asked Apple to modify this handset to disable the data wiping feature, so the CIA can then just keep throwing passwords at it until it unlocks. Clearly, this is going to have no physical effect on any other handset anywhere else in the world. So what’s Apple’s problem?
If Apple helped the CIA break in to the handset, Apple can no longer claim that its handsets are invulnerable. Terrorists, fraudsters and anyone up to something will know that the authorities can get at Apple data even more easily than if it was stored on iCloud. Note well: the fact that Apple hasn’t produced the mod needed to do this (publicly), doesn’t mean that its not possible right now; and it may even be happening. But Apple wants to maintain the illusion that it can’t.
Put another way, it’s easy enough to bypass the locks on a front door. You just need a large enough sledge hammer. Doubt this? Look at the footage of a police raid taking place – a few burly coppers with a battering ram and it’s open in seconds. Apple is selling locks and trying to pretend there’s no such thing as a sledgehammer.
So why, might one ask, don’t the US authorities stop messing around and get the court order enforced? Are they really scared of Apple?
What’s really worrying about this situation is that “civil liberties campaigners” and some corporate America is rushing to put out statements in Apple’s defence. In other words, big business reckons it’s above the law made by the people using a democratically elected government.
Well that’s what it looks like. Criminals apparently from Bangalore have been distributing loads of malware spams from addresses like Nich***.Davi**.5208@vosa.gsi.gov.uk, and they’re getting through spam filters.
The messages continue:
Subject: DVSA RECEIPT
Good afternoon
Please find attached your receipt, sent as requested.
Kind regards
(See attached file)
Fixed Penalty Office
Driver and Vehicle Standards Agency | The Ellipse, Padley Road, Swansea,
SA1 8AN
Phone: 0300 123 9000
Find out more about government services at www.gov.uk/dvsa
**********************************************************************
This email and any files transmitted with it are confidential and
intended solely for the use of the individual or entity to whom they are
addressed. Any views or opinions presented may be those of the
originator and do not necessarily represent those of DVSA.
If you were not the intended recipient, you have received this email and
any attached files in error; in which case any storage, use,
dissemination, forwarding, printing, or copying of this email or its
attachments is strictly prohibited. If you have received this
communication in error please destroy all copies and notify the sender
[and postmaster@dvsa.gsi.gov.uk ] by return email.
DVSA's computer systems may be monitored and communications carried on
them recorded, to secure the effective operation of the system and for
other lawful purposes.
Nothing in this email amounts to a contractual or other legal commitment
on the part of DVSA unless confirmed by a communication signed on behalf
of the Secretary of State.
It should be noted that although DVSA makes every effort to ensure that
all emails and attachments sent by it are checked for known viruses
before transmission, it does not warrant that they are free from viruses
or other defects and accepts no liability for any losses resulting from
infected email transmission.
Visit www.gov.uk/dvsa for information about the Driver Vehicle and Standards Agency.
*********************************************************************
The original of this email was scanned for viruses by the Government Secure Intranet virus
scanning service supplied by Vodafone in partnership with Symantec.
(CCTM Certificate Number 2009/09/0052.) This email has been certified virus free.
Communications via the GSi may be automatically logged, monitored and/or recorded for
legal purposes.
This all looks pretty genuine – they probably copied it verbatim with the exception of the “good afternoon”.
The payload is a Microsoft Word document with macros, but I’ve yet to figure out exactly what it’s doing. In the parlance of the security “industry” it’d be a zero-day exploit, but that’s not interesting. What did come as a bit of a surprise to me is that GSI doesn’t seem to bother with SPF records, which would have helped detect the fake. Bayesian analysis throws up nothing, and it’s coming from a clean IP address that has yet to be listed. The only things wrong with it are that there’s no reverse lookup, and no SPF on vosa.gsi.gov.uk to flag it as dodgy.
The civil service clearly hasn’t got this security business clear yet.
I was woken by Radio 4 this morning with news that HSBC (and First Direct) will be rolling out voice identification software as a replacement for the “cumbersome” password-based system currently in use. I’ve been using this cumbersome system for more than twenty years, and I can’t say I have any problem with it – ten seconds and you’re in; and time has proven it reasonably secure.
But this new biometric “voice-print” system sounds a tad more dodgy to me. It comes from Nuance Communications, and apparently it checks over 100 unique identifiers in someone’s voice, including speed and behavioural features and maps the sound it’s hearing back to physical features such as the shape of the larynx and nose. The technology might be better remembered as Dragon Dictate from the 1990’s, although Nuance has been working on the biometric aspects for some time, and recently announced Santander was going to use it in Mexico.
I’m naturally suspicious of any biometric identification method apart from retinae scans, having looked at many such schemes over the years. They’re generally vulnerable to amounts to “replay” attacks. Fingerprint or face recognition can usually be fooled relatively simply with a picture of the real thing. So what’s to stop a replay recording of someone’s voice? Nothing, as far as I can tell.
When the BBC asked about recordings being played back they were told that any recording process would lose the subtleties of live speech, and the BBC seemed happy with that. Well I’m not! The way telephones work these days, your voice is sampled, encoded in to very few bps and sent. How is this going to look any different to a recording? You can store and repeat a section of telephone call digital data easily enough and it’s bound to be indistinguishable.
I can see some solutions – the system could ask you to repeat some random phrase back instead, and word recognition could determine whether you said the right thing after the biometric recognition matched the voice print. But this isn’t the answer the BBC got.
I’m awaiting more information…
HSBC had a bad January with cyber-attacks. Is this some ill-conceived scheme to try and change the news agenda?
I’ve seen a lot of this before, and the criminals generally ask for a sum that it’s easier to pay than mess around trying to repair the damage. In other words, £500 is normal but £1M is not. For this to be credible, someone would have had to target them specifically, and come up with a plot to damage a lot of data in one go. This is possible if one PC has R/W access to a lot of files on a server, but for the criminals to expect to do this value of damage the council would have to be pretty incompetent and the criminals would have had to know this for certain. (What am I saying?)
From the BBC report there are a couple of interesting lines:
“The authority said it was working with its computer security provider to apply a fix to its systems.”
Hmm. So who is their computer security provider? If they have one that’s any good, the network would have been set up to avoid such wholesale damage. Serco took over the Council’s IT operations in April 2015. in a £70M+ deal. Whether the outsource company has outsourced the “security provision” is a little harder to know.
Further down the BBC article it says:
“Chief information officer Judith Hetherington-Smith said only a small number of files were affected.”
If that was true, restore them from a backup or take the hit – how can a small number of files be worth £1M?
Locking down the network after such an attack is a good idea, and this would disrupt office services for certain. But something just doesn’t add up here. It’s possible that the £1M ransom demand has been made up, to cover their embarrassment. Or it could just be sloppy journalism by the BBC – no facts checked and a story about some ransomware being blown out of all proportions. Serious news media haven’t had much to say on the subject. The Register has covered it, but has not repeated the £1M ransom claim.
The FSF thinks Netflix is wrong to protect artist’s right using DRM
Earlier this month at CES, Netflix’s chief product officer Neil Hunt stated that his company’s policy on subscribers accessing content over a VPN remained unchanged. That’s to say that they ask customers not to do it, as it can bust licensing restrictions on content. Neflix is probably the largest provider of streamed TV programmes around the world, now operating in a claimed 190 countries.
I’m not a fan of Netflix – they’re big campaigners for “Net Neutrality”, meaning that all content must be treated the same and ISPs can’t charge more or slow down particular traffic. As their content is not for the public good, and yet accounts for about 40% of the world’s public Internet traffic, they would say that, wouldn’t they? As media organisations such as the BBC (iPlayer) are in the OTT game, the fact that this is a business model where the bulk of the costs are paid for by all Internet users whereas the profits go to the streaming service is not generally mentioned in the popular press. In other words, they profit from the ISP’s investment without contributing anything back. Amazon Prime is another good example.
Anyway, the content that Netflix streams is licensed from content producers, who have good reasons for licensing it on a geographic basis. A TV programme broadcast in one country becomes harder to sell to networks abroad if it’s already available via streaming, and upsetting the status quo won’t be good for content producers. This will leading to less investment in good programming. Netflix is “campaigning” to change this, as though the public, including its customers, have some kind of rights that are being denied. It would, of course, help Netflix’s commercial interests if regional licensing didn’t exist – at least short-term.
That aside, I was amused to see that Neflix’s latest pronouncement, in a company blog post by David Fullagar (VP of Content Delivery Architecture) a week after the CES announcement, that it would now be clamping down on its customers use of proxies or VPNs to smuggle streamed data across boarders. One might surmise that the content providers, many of whom are also local broadcasters, didn’t appreciate Neil Hunt’s complacent sounding comments. The status quo he was defending was basically an weakly enforced contractual prohibition on its customers streaming through a proxy. A actual enforced ban would result in a loss of revenue to Netflix, or if you’re less cynical, would go against the company’s stated aim of “all content free to all (subscribers)”.
But in spite of the soothing words to calm the outrage of its content suppliers, what can Netflix actually do about this? How do you block your customers using a VPN?
It seems to me that it’s impossible to tell whether you’re sending UDP packets to an IP address that’s actually a VPN. It can’t be done. There can be any number of endpoints behind one IP address (an asymmetric NAT LAN), and any number of VPN connections to who-knows-where. And they’ll all appear as one IP address, and the traffic will be indistinguishable.
So how do streaming companies block VPNs now? By having a list IP addresses used by published ones, and that generally means commercial ones. Okay, that might work for the public/commercial VPNs. I shan’t be shedding too many tears if they’re blocked, because they’re making money out of license-busting, which is wrong.
But consider this. Supposing you pay the BBC for a TV license but live abroad for part of the year. You have a moral right to view the content you’ve paid for, and could do so using iPlayer. The only problem is that iPlayer may detect you’re outside the UK by your IP address, and stop you. The solution? Put a proxy server on the network in your house in the UK and connect to it when you’re abroad. I have evidence that this happens a lot.
This can also be done immorally. People in one country with relatives living abroad can set up such a proxy for their friends and relatives to use, and Netflix will be none the wiser. Even if Netflix did suspect an IP address of having too much traffic, what could they possibly do about it? Contact the owner and investigate? How would they even find the owner?
Many ISPs use dynamic addresses in order to charge more for a static one to business customers, with the effect that you don’t know who’s using what IP address today. If you do find a suspected VPN, tomorrow it’s IP address will have changed to one of millions, all used by normal domestic customers.
Finding the many small, private VPNs is going to be impossible. One method might be to probe an IP address to see if a VPN port was open. This is no proof that it’s in use, and no proof that it’s not used for one of the many purposes that a VPN was designed for. And even if they were to try it, it’s simple to restrict access to the VPN ports to your friends abroad. And besides, probing an IP address for an open port without permission is illegal.
The only other method I can think of that would work is to examine the traffic to/from an IP address and see if there’s a correlation between outgoing packets and incoming data from one of Netflix’s servers. But Netflix can’t do that; only an ISP has the technical ability to examine traffic on a particular subscriber’s line. And those are the ISPs that Netflix is abusing by loading them with 40% of their traffic without contributing to the cost. Good luck with that.
Since I reviewed iZettle’s new contactless card reader there have been a few updates to the App, and after the initial teething problems I’m happy to report that it’s been working flawlessly hereabouts.
iZettle Bluetooth Card Reader
The latest update is to support contactless payments on American Express. This came as a bit of a surprise, as I assumed it already did! It just goes to show how important Amex is…
You need to do a firmware update. You get this by connecting to your tablet/phone and running the iZettle App. Then go to Settings/Card Readers and select Update. I’ll let someone else try it first, as I can live without the functionality for a while longer.
This does not, of course, work on the freebie iZettle reader – only the Bluetooth one that you pay money for. Don’t be cheap – it’s good!
This update means support for contactless covers Visa, MasterCard, Applepay and Amex. I have to say that I’ve yet to find a card in the UK it couldn’t use, one way or another.
This week that ParentPay, the Microsoftie payment system used by many schools, rolled out a web site update to support an even more limited range of browsers. This included dropping support Internet Explorer before 9 for “security reasons”.
By coincidence, in the same week Microsoft trumped their loyal fanobois at ParentPay by announcing that everything prior to version 10 was hereby deemed unsafe. ParentPay has yet to comment.
However, the notion that any version of Internet Explorer is “safe” is stretching the truth badly. All the mainstream browsers are dodgy; they all support unsafe scripting and embedded code. Microsoft may have the worst reputation, but they’re all undermined by their code and add-ons – and host operating system, to be fair. Only a few niche browsers, that don’t support things like JavaScript and ActiveX, can be considered safe; and those are the ones that ParentPay refuses to support because they don’t allow “rich content”. (And their developers are Microsoft fans). It’s definitely a case of form over security, yet again.
As an illustration of just how feeble their new browser support policy is, here’s a list of those they’ll accept, taken from their web site:
Chrome 35 or higher
Firefox 30 or higher
Internet Explorer 9 or higher
Safari 6 or higher.
The the the the That’s All Folks!
Schools should be seriously considering their relationship with ParentPay, given the cost and inconvenience they’re forcing parents to go through in order to use it. Analysis of the traffic across my servers suggest that IE has around a third of the browser market. Of these, more than half are using IE 9 or earlier.
ParentPay’s assertion that this will only affect a “..small proportion of parents” may be literally true, but it’s disingenuous. Let’s do some simple arithmetic. Say there are 1500 parents in a secondary school. A third of these use IE – that’s 500. Half of these use an old IE (on an old PC) – that’s 250/1500 parents at each school who’ll be grossly inconvenienced. Cancel the fraction out and it’s 1/6, which could be described as a small proportion, but it’s still 250 per school.
The number of people who would be using”unsupported” browsers on tablets or mobile devices is probably very high. Anecdotally, parents have access to a PC somewhere that they currently have to go to in order to use ParentPay. Many would rather use a tablet.
It’s about time someone set up an alternative to ParentPay and schools were educated in to the benefits of open standards.
First off, can I be clear about one thing – endpoint virus scanners don’t make your computer “secure”. A lot of the most dangerous stuff gets past them, but trusting lusers believe they’re safe and will therefore take risks they outerwise wouldn’t. See my posts and academic papers passim ad nauseam. Now that’s out of the way, I favour Microsoft Security Essentials (or Microsoft Endpoint Security) on Windows as I find it less likely to make the system unusable. I don’t recommend it, except as the least-worst option.
On with the problem…
Sometimes, especially in the last year or so, I’ve found Security Essentials will stall when its doing a background scan. You may not notice its done this, but some symptoms are that web browser file downloads won’t work (it’ll download 100% but never finish) and the PC won’t hibernate automatically using the power-saving settings.
I’ve looked for solutions to this, as well as searching the web for an answer. You’ll often see people posting (without references) that this is bug and Microsoft are working on, or have now fixed it. I’ve tried theories myself to see if it’s caused by compression or archive formats causing a decompresser to break (I’ve noticed this often fits the facts), but this is little help when finding a solution, and even then it sometimes still hangs when the option to check compressed files is turned off.
What I’ve yet to find is anyone giving a real solution, so here it is:
Deinstall Security Essentials.
Download and install Security Essentials.
I’ve never known this not to work. On the other hand, I’ve known all the other theories you see posted on forums fail to work pretty consistently.
There’s a bug in all by the most recent versions of the Android operating system that can theoretically allow attackers to take over the device simply by viewing a web page or downloading a media file. It’s actually in the Stagefright library, and was the talk of Black Hat last August. Then it was considered hard to exploit, but security researcher Hanan Be’er at North-Bit in Israel has now 
Reports are that Lincolnshire Council has been shut down for four days because it’s been targeted by ransomware
