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Flash Crash (Adobe version)

AGet the dobe Flash (the browser plug-in) is notorious as a security risk, and the current batch of known exploits does nothing to improve it’s reputation. Sorry Adobe.
CVE-2016-1010 is the latest biggie, as it allows remote code execution on all but the very latest plug-in. There’s also CVE-2015-8651, CVE-2015-7645, CVE-2016-0963 and CVE-2016-0993 to worry about.

You should, of course, make sure that you have the latest plugging installed on your browser. Unfortunately the version numbering system varies by platform so I can’t easily tell you which you need.

When looking at multifarious Adobe Flash vulnerabilities in the NIST database I’m always amused to note that it appears to be written in Coldfusion. For the last ten years that’s been Adobe Coldfusion. Oh my!

 

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FreeBSD sysarch kernel panic vulnerability

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 problem was found by Core Security, and they have provided an excellent write-up here.

But if you want it in plain English:

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:

Please generate and paste your ad code here. If left empty, the ad location will be highlighted on your blog pages with a reminder to enter your code. 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.

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Governments’ hacking fantasies

It’s silly season again.

Yesterday George Osborne warned that Islamists were tooling up and planning deadly cyber-attacks against the UK, targeting critical systems like ATC and hospitals, as he announced government spending on countermeasures would double from about £200M to £400M a year. Mr Osborne shown a rather tenuous grasp of technology in the past, and I fear he’s been watching too many Hollywood movies when forming his current opinion.

I know a bit about ATC, and the chances of a jihadi disrupting NAS over the internet are slight. Damaging aviation is much easier by more direct means.

Likewise, while I have little time for the design of NHS computers systems, even they’d be hard to seriously disrupt. So difficult that it really wouldn’t be worth the bother. If you want to knock out a hospital, blow up the generators and electricity feed – it’s obvious. About the only systemic damage you could do remotely would be to mess up central databases, but these seem to get messed up regularly anyway, and the world goes on.

But this seems positively sane and sensible compared to today’s report from the “US-China Economic and Security Review Commission”. They’re all exercised about those nasty Chinese guys pinching trade secrets by hacking in to US companies and their government agencies. I’m sceptical about the idea that the Chinese government is behind this, and the Commission has weakened the credibility of their claims with their suggested response to the activity:

Yes folks, their suggestion is that Americans hack in to the Chinese systems and steal back or delete the stolen data. How exactly does one steal back data? And do they really think it’s possible to locate, identify and delete stolen data found in a foreign country. Deleting all copies of data from a local system is hard enough, and if the IT department knows its stuff, it’s impossible as it won’t all be on-line.

Whilst there’s plenty of evidence that people in China, and possibly the military, are engaged in cyber-espionage, this idea reads like the plot of another Hollywood movie of the type George Osborne seems to have been watching. Everyone in the security world knows that the majority of criminal activity on the Internet actually comes from…. the USA. This doesn’t mean the US government is behind it – by the sound of the advice they’re getting, they wouldn’t know how.

People like me have been saying that cyber-crime is (going to be) a big problem for many years now, and I welcome governments waking up and taking it seriously at last. The private sector has done spectacularly badly, as the money is in the superficial stuff, and real security gets in the  way of profits. It’s just a shame that governments have woken up and are groping groggily around in the dark.

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Smart TVs attacked over the airwaves

A group of researchers from Columbia University have published the results of some experiments with mixed mode digital TV broadcasts here.

The problem is that the new but widely implemented HbbTV standard allows HTML to be embedded in with the picture data. What could possibly go wrong?

Well apart from the fact you only need an encoder and transmitter to mess up all the sets in range by sending them HTML spam, the Columbians reckon that with the right HTML you can turn people’s tellies into a botnet and attack targets through their internet connection. I’m not yet convinced this will work in practice, but building a web browser in to anything has always been risky when it implements more than plain HTM. It’s always been possible to broadcast alternative TV and radio signals over the top of legitimate channels, but generally, it doesn’t happen in practice.

 

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eBay security problem in February – just noticed!

Well, it had to happen. Today eBay announced a serious security compromise. Apparently someone’s got hold of employee login details that allowed access to databases containing customer names and contact details, together with a password hashes.

Should anyone be worried?

Well, a hashed password isn’t a password but it’s possible to crack, especially if it was a weak one (i.e. a word or two words conflated, with a digit on the end and possibly a full stop). eBay says that there’s no evidence of anything fraudulent transactions. Yeah, great. The problem is going to come when people have used the same password elsewhere, like on their PayPal account, bank account or somewhere important – armed with their contact details and a crackable password, those people could be in real trouble.

eBay is due to email everyone very soon to ask them to change their password. It’s called shutting the stable door once the horse has bolted – this data may have been in the hands of the criminals for a couple of months now. You don’t need to change your eBay password; you need to change the password on every system that used it.

The sooner this antiquated means of verifying identity was replaced by secure public certificates, the better – by the punters won’t understand how those work.

So what does this mean? Your password was secure but now it isn’t? No. It was only secure before if you trusted the eBay employees. And a find upstanding bunch they are.

Next, of course, the scammers are going to spam everyone with phishing eBay credential change emails. And when this hits the news, who’s going to disbelieve it. eBay really needed to manage the news dissemination better.

 

 

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Internet Explorer scare

I’m getting a lot of calls about Internet Explorer. Apparently it’s got another security bug. It must be true because it was on the BBC.

Well it’s partly true. The bug is actually in ActiveX, which is Microsoft’s dodgy web browser application format. All browser application formats are dodgy. Allowing web sites to download code and run it on your PC is just a bad idea.

I’ve said it before and I will say it again: just turn off ActiveX. That said, looking at the details of this particular vulnerability it doesn’t appear very easy to exploit. I suspect it’s getting more of a mention than it deserves as Microsoft isn’t going to patch it for IE6 or Windows XP for the first time, or so they say.

Hmm. What can Microsoft be thinking? Either they patch this regardless, or lose a further share of the browser market to Chrome – and another nail in the coffin of Active-X.

 

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Heartbleed bug not as widespread as thought

Having tested a few servers I’m involved with, many of which are using old or very old versions of OpenSSL, I can’t say I’ve found many with the problem. You can test a server here: http://filippo.io/Heartbleed/ on a site recommended by Bruce Schneier.

So what’s going on? Does this affect very specific nearly-new releases. This story could turn out to be a serious but solvable problem, and a media panic. I recall spending most of 1999 doing interviews on how the “year 2000 bug” was going to be a damp squib, but it’s early days yet.

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Internet Explorer – new vulnerability makes it just too dangerous to use

There’s a very serious problem with all versions of Internet Explorer on all versions of Windows. See here for the osvdb entry.

In simple terms, it involves pages with Flash content, and all you’ve got to do is open a page on a dodgy web site and it’s game over for you. There’s no patch for it.

Microsoft’s advice can be found in this technet article. It’s pathetic. Their suggested work-around is to deploy the Microsoft Enhanced Mitigation Experience Toolkit (EMET). Apparently this is a utility that “helps prevent vulnerabilities in software from successfully being exploited by applying in-box mitigations”. Microsoft continues “At this time, EMET is provided with limited support and is only available in the English language.”

Here’s my advice – just don’t use Internet Explorer until its been fixed.

Update

21-Sep-12

Microsoft has released a fix for this. See MS Security Bulletin MS 12-063.

If you have a legitimate copy of Windows this will download and install automatically, eventually. Run Windows Update manually to get it now – unfortunately it will insist on rebooting after installation.