New Research Shows How Easy It Is To Get Weapons Or Explosives Past Backscatter X-Rays

from the feeling-safer? dept

Mon, Dec 13th 2010 8:40am — Mike Masnick

We've heard the various stories of folks getting weapons past the TSA's new scanners -- such as Adam Savage's famous video from earlier this year, or the more recent report of a guy getting past the scanners with a 6" hunting knife. Both of those stories appeared to just be about the bag scanners missing stuff on the conveyor belt. But what about the new backscanner x-ray machines? Well, Jay points us to some new research by two UCSF professors that indicates getting dangerous weapons or explosives past the new machines isn't that hard. They look at how the machines work and the various images currently out there, as well as their understanding of x-ray technology, and point out that since the x-rays need to pass through your body, if you flattened out some plastic explosives, they probably won't be noticed, or if you just put the weapon on your side the new machines probably won't spot them:

It is very likely that a large (15�20 cm in diameter), irregularly-shaped, cm-thick pancake with beveled edges, taped to the abdomen, would be invisible to this technology, ironically, because of its large volume, since it is easily confused with normal anatomy. Thus, a third of a kilo of PETN, easily picked up in a competent pat down, would be missed by backscatter "high technology". Forty grams of PETN, a purportedly dangerous amount, would fit in a 1.25 mm-thick pancake of the dimensions simulated here and be virtually invisible. Packed in a compact mode, say, a 1 cm�4 cm�5 cm brick, it would be detected.

The images are very sensitive to the presence of large pieces of high Z material, e. g., iron, but unless the spatial resolution is good, thin wires will be missed because of partial volume effects. It is also easy to see that an object such as a wire or a boxcutter blade, taped to the side of the body, or even a small gun in the same location, will be invisible. While there are technical means to mildly increase the conspicuity of a thick object in air, they are ineffective for thin objects such as blades when they are aligned close to the beam direction.

Feeling safer? Once again, this isn't to say that there shouldn't be a security screening process, but if we have to go through all this trouble, shouldn't we at least have a system that is at least somewhat effective?

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Filed Under: backscatter, security, tsa, x-rays
Companies: tsa

33 Comments

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AJ, 13 Dec 2010 @ 9:13am

O boy.....
Now were going to all have to walk thru the pr0n machine nude in case were hiding something? I really won't feel safe until we use the "enhanced, combined, total body check system" (patent pending), consisting of a scan machine, metal detector, pat down, shoe removal, bomb sniffing dog, proctologist, gynecologist, E.N.T. specialist, psycologist, belly button lint detector... would someone please think of the children??
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anothermike, 13 Dec 2010 @ 9:19am

it works great!
These machines are working exactly as they were designed to... they funnel taxpayer money into the pockets of political friends more efficiently than almost any other graft out there.
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Anonymous Coward, 13 Dec 2010 @ 9:34am

boom
just build a fat suit out of plastic explosive.
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Anonymous Coward, 13 Dec 2010 @ 9:41am

New research shows that no security system is perfect.

They had to do research to prove it?

The idea of any security system is not 100% perfection, that is a straw man concept at it's finest. Each of the parts of security work together to provide the best results under the circumstance.

Prisoners in the state and federal systems are still able to smuggle drugs and manufacture weapons while incarcerated. All of the security there can still be gotten around by someone who is very, very determined.

But the alternative is to significantly limit security, say back to just having someone look in your carry on bag and tell you to have a nice day. If the effort is wasted, why do any of it?

If you can answer that question, you will understand why you do the rest of it too. All of the people screaming "graft" or "lining the pockets of their friends" probably has never lost a friend or relative to a violent act.
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Anonymous Coward, 13 Dec 2010 @ 9:42am

Re: boom
Lol.
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Steven (profile), 13 Dec 2010 @ 9:44am

You're not saying it, but I will
"Once again, this isn't to say that there shouldn't be a security screening process..."

Why do we need to have a security screening process? Are planes really more dangerous than anywhere else? Do we put security around a bus or train?

I would say get rid of the whole deal, maybe put two trained security guards on each plane. Passengers won't sit around anymore. Also it shouldn't be the governments problem to solve.

The mindset that we absolutely must have some security to get on a plane I find very suspect. I wouldn't say we absolutely shouldn't have security, but leave it up to the airports and airlines to find the right level, even if that level is nothing.
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Anonymous Coward, 13 Dec 2010 @ 9:49am

Re:
I'm going to try to be civil. Mo amount of security will stop ALL of the attacks, and these new "efforts" have been shown to miss MOST of the possible situations. I have not lost anyone violently, but if I do, I won't be clamoring for MOREMOREMORE. The first post, albeit exaggerated, is a good representation of the direction of the security theatre.
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Chronno S. Trigger (profile), 13 Dec 2010 @ 9:51am

Re:
"If the effort is wasted, why do any of it?"

That's a damn good question. How about you answer it? Why the hell would we waste the tax payer money, time, or dignity on a system that doesn't work?

"probably has never lost a friend or relative to a violent act."

Yes I have, insensitive asshole. I'm not asking for every single driver to get stopped every 5 miles just to catch that one in a million drunk driver, why the hell are we wasting time and effort on something that's so much less likely to happen.
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Anonymous Coward, 13 Dec 2010 @ 10:00am

Re: it works great!
Hit the nail square on the head there. That is absolutely correct. When it's shown that trained dogs and properly trained screeners would be not only more effective but cheaper, the backscatter machines start looking mighty suspicious.

It would be nice if this country (government, really) would pull its head out of its PC, liberal ass and handle air travel like Israel does. There is one type of people who tend to blow our planes up, concentrate on them.

God, how long does this charade have to last? Until our finances and liberties have evaporated? Christ, air travel is a privilege, not a right. Don't like being singled out? Take a bus. Or better yet, come to terms that we are vulnerable and this knee-jerk reaction prone government will use that as an excuse to bilk us out of our tax dollars and freedom. Still don't like the idea? Just wait. Until something changes, it will just get worse.

Pretty soon, you wont be able to drive your car down the street without being x-ray'd. ...oh, wait.

/rant
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Steven (profile), 13 Dec 2010 @ 10:09am

Re: Re: it works great!
I with you on all but one.

"air travel is a privilege, not a right"

Freedom of movement is a right. It has been upheld in court (I don't know the case off the top of my head) that undue burdens put on air travel violate that right.

I'm fairly certain a lawsuit aimed at ridding us of the backscatter and 'fun' patdowns could succeed if properly executed. I suspect it would have to be from somebody who didn't fly because of them in order to make it into the courts.
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penstock, 13 Dec 2010 @ 10:21am

'Security Theater' as a deterrent
How many terrorist attacks against the airlines have occurred over the past 9 years? I can recall a couple - and in both cases, the terrorist turned out to be an "idiot" incapable of setting of their own bomb. Two cases? In 9 years? Really...

Most of the current airport screening is intended to serve as a 'deterrent' to an act of terrorism, and not necessarily to detect an act in progress. However, perhaps the flaw in thinking here is the principle of 'deterrence' itself - only a reasonable, rational, and cautious person would be deterred by any of this - a "desperate crazy" person, or an "idiot" would hardly notice this obstacle to their plan.

So, once again, the argument comes back to the question: are all of the current screening techniques really effective at stopping and actual act of terrorism - or are they merely 'theater'?
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Anonymous Coward, 13 Dec 2010 @ 10:23am

Re:
New research shows that no comment system is troll proof perfect.

They had to do research to prove it?

The idea of any comment system is not 100% perfection, that is a straw man concept at it's finest. Each of the parts of a comment system work together to provide the best results under the circumstance.

[insert pointless, random analogy here. Gain bonus points for mentioning cars, Hitler (oh no he di'int), freetards or communists.]

But the alternative is to significantly limit commenting, say back to just having no comments at all. If the effort is wasted, why do any of it?

[insert random, whining closing statement here.]
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Gabriel Tane (profile), 13 Dec 2010 @ 10:51am

Re: Re: Re: it works great!
Freedom of movement is a right. It has been upheld in court (I don't know the case off the top of my head) that undue burdens put on air travel violate that right.

I'd really be interested in reading that. I'm a big fan of the debate between granted rights and assumed (or demanded) rights. I did a basic search and couldn't really find any references to court cases that show the TSA's actions are unconstituional on the grounds that they block freedom of travel.

The real kicker is that the TSA is not a required service. Airports can say "nah, we'll hire someone else" and there was a recent story where one airport did (San Diego, I think... could be wrong).

But seriously, I'd love to read up on that law if you ever find it.
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Steven (profile), 13 Dec 2010 @ 11:06am

Re: Re: Re: Re: it works great!
The wikipedia page on 'right to travel' is pretty good.

http://en.wikipedia.org/wiki/Freedom_of_movement_under_United_States_law

The case I see sited most often is the US v Guest case (which in my mind the travel part of that is a little interesting).

I read a pretty good breakdown of how one might find the TSA practices unconstitutional, but I can't find it right now. If I find it again I'll be sure to post it on a future TSA article (I'm sure we'll see more :) )
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Anonymous Coward, 13 Dec 2010 @ 11:24am

Re: 'Security Theater' as a deterrent
Two cases in nine years, sure, but how many attacks/bombings were there in the DECADES before 9/11? When they were far more vulnerable? The fact that the sun hasn't explodes doesn't mean anything we're doing is acting as a deterrant.
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zm, 13 Dec 2010 @ 11:42am

Re: Re: it works great!
> There is one type of people who tend to blow our planes up, concentrate on them.

Before getting too hung up on profiling, go look up Anne Marie Murphy, then think again. Furthermore, if you want airline security like Israel's, be ready to answer questions along the lines of who you are, where do you live, what do you do, who is your spouse, what is the purpose of your trip, where are you staying, your friends names and addresses etc.

But I do agree that the porn scanners are a waste of money.
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Gabriel Tane (profile), 13 Dec 2010 @ 11:50am

Re: Re: Re: Re: Re: it works great!
That's the one I was reading. I can see how it sets up the arena for all this theater to result in such a ruling. I can't wait to see it happen.

I just don't want people to mistake layman interpretation as a granting of rights (which I see happen all too often).
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Anonymous Coward, 13 Dec 2010 @ 11:52am

Re: Re: Re: it works great!
The Murphy case is a good example of why we should still have moderate screenings, particularly of baggage, but you couldn't cite it as an argument against profiling, just against "nothing but profiliong."
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Meee, 13 Dec 2010 @ 12:01pm

Weird
Just out of interest, how come wikileaks gets slammed for endangering national security, but studies/research like this, which basically say "Hello, here is how to smuggle dangerous weapons past our security checkpoints and not get caught" don't?

This study right here has *far* more potential for harm than anything wikileaks has released so far.
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Anonymous Coward, 13 Dec 2010 @ 12:06pm

Re: Weird
This study doesn't directly make politicians look bad.

Oh, sorry; you really thought the reaction to WikiLeaks was because of security concerns?
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Not an electronic Rodent, 13 Dec 2010 @ 12:11pm

The thing I find interesting...
...is that but getting so invasive and creating a debate out of it, what's effectively happened is that these machines are actualy *less* efective that their "predecessors" and even the "security theatre" element is starting to fail.

Everyone grumbled about detector arches and x-ray machines etc but no one really cared and it was just generally assumed that detected good stuff, which is why they were there. So out of that you go thte theatre element - a nice fuzzy warm feeling if you don't think too hard.

Now, people are starting to wonder and the process itself it making the news and now we get reports like this (which let's face it probably exist for most of the other technologies), and people are looking. So what happens is soon everyone knows they don't actually detect anything much useful so the warm fuzzy feeling evaporates - security theatre purpose over.

So why use these things again?
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Anonymous Coward, 13 Dec 2010 @ 12:44pm

Re: Re:
Think about it though: How would you feel if all drunk driving laws were removed because they aren't 100% successful? There is a balance between public safety and personal rights, and those change and adjust over time.

If signfiicantly more people were driving drunk and killing people, you know that your local police / state/ whatever would almost certainly step up enforcement, education, and check points. Would you prefer they throw up their hands and give up altogether?

After all, it is just "security theater", no?
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Anonymous Coward, 13 Dec 2010 @ 12:50pm

These new airport security procedures are exactly like DRM. The people most inconvenienced are the paying customers that do the right thing. People with bad intentions do their homework and then find a way around the security measures.

This will leave you with pissed off customers and no real security.
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Mr Big Content, 13 Dec 2010 @ 1:35pm

Put The Troublemakers On The No-Fly List
This subversive kind of so-called �research� is doing nothing to improve our security, and shouldn�t be conducted by unqualified no-name hobbyists.
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Marcel de Jong (profile), 13 Dec 2010 @ 2:00pm

Re: O boy.....
just undress... yes, completely, drop those skivvies!

or 'better' yet, fly naked.
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James, 13 Dec 2010 @ 2:29pm

Per Robert Stack
"Full body cavity search for everyone."
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Anonymous Coward, 13 Dec 2010 @ 3:51pm

Re:
"If you can answer that question, you will understand why you do the rest of it too. All of the people screaming "graft" or "lining the pockets of their friends" probably has never lost a friend or relative to a violent act."

Do you let grief and pain paralyze you?
We move on, we do our best and that is all there is to it.

More and more security won't stop a determined opponent, but will stop society.

Maybe we should just stop planes from flying, is the sure way to not having any problems no more.

Keep doing this ridiculous circus and that will happen anyway, people just won't get into an airplane, it was bad before, now the financial situation must be getting worst.
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Anonymous Coward, 13 Dec 2010 @ 3:58pm

In the meanwhile terrorists have moved on to other targets.

Sweden recent attack attempt just proved that you can explode anything near a group of people anywhere.

Planes where good for a one off cruiser missile attack now since they don't have a way to get control of an airplane anymore they moved to shopping malls.

Will the U.K. install porno scans at every bus stop?
Will Sweden put giant porno scans at every road?

How about sea ports and trains?

How about getting a job as a janitor in some building and planting explosives in the building at the course of a year and detonate it at Christmas?

Security is good, over thinking it is bad.
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Anonymous Coward, 13 Dec 2010 @ 4:00pm

At some point we must just accept loses and move on.
It is tragic, it is sad, it is painful, but the alternatives are just as bad.

Where do we draw the line?

I believe we reached the limit of the acceptable.
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Anonymous Coward, 13 Dec 2010 @ 5:13pm

Re: Re: Weird
I do find it kind of amusing that the "serious" political backlash against Wikileaks only started after leaks that were personally embarrassing to bureaucrats.

Leaks about the military? Some tepid whining and everyone stopped worrying about it a few days or weeks later.
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Anonymous Coward, 13 Dec 2010 @ 5:41pm

forty grams of PETN, a purportedly dangerous amount, ...

Forty grams of explosive will comfortably fit in one's rectum. It would fit in any ordinary vagina. There is no perfect security without full body cavity searches of all passengers.

On the other hands, tens of kilograms would fit into a suitcase dropped off at the passenger screening line.

Somewhere we have to figure out the difference between a crime and a national security threat.
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nasch (profile), 14 Dec 2010 @ 7:11pm

Re: Re: Re:
If anti-drunk-driving campaigns were extremely expensive and only marginally effective, I hope we would see similar calls for a smarter approach.
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nasch (profile), 14 Dec 2010 @ 7:15pm

Re:
Forty grams of explosive will comfortably fit in one's rectum.

Comfortably - are you sure? ;-)
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