Visit ArabTopics.com

IMSI Catching: Phone surveillance measures and countermeasures go mainstream

phone-and-simcard-1280x720-istockphoto

Activism: The German newspaper Die Zeit has a long feature this week about IMSI catchers and their countermeasures, words that were long heard only in countersurveillance cultures at Black Hat and Defcon. Observing this phenomenon make the jump from the obscure to the mainstream tells us a lot about the years to come: surveillance and countersurveillance will be a cat-and-mouse game for quite some time.

Most people have heard of their IMEI, their phone’s unique identifier. It’s short for International Mobile Equipment Identity, and a lot of people learn how to read this number. Originally, it was produced by typing ×#06# on your phone, a sequence that amazingly still works, but it’s also on the phone receipt, in the menus, and in a number of friendlier places. This is the number you can insure, and this is the number you can report stolen to brick the phone.

A more secretive number is the IMSI, the Subscriber Identity, which identifies not the phone but the SIM card inside the phone. In most parts of the world, you’re expected to buy these separately from the phone, and you can replace the SIM card to change carriers but keep the same phone. In some other parts of the world, where telco carries have exercised regulatory capture and have a dysfunctional market, the SIM is typically card prebaked into the phone, and in these countries, you might never have seen it – but it’s still there, identified by the IMSI.

There are many good technical reasons to keep this number a secret. For example, any reconfiguration instructions sent to the phone from the carrier – so-called Over-the-Air provisioning — must be signed cryptographically with the IMSI of the current SIM card, in order to prevent fraudulent configuration. It’s also the number used when the phone contacts the carrier network, and therefore, anybody intercepting that handshake will see the IMSI.

This is the technology used in so-called IMSI catchers. When there is a large number of people in an area that the regime — police or other forces — want to keep tabs on, they deploy high-powered fake celltowers that the phones connect to, believing that these fake celltowers are their carrier’s. The fake towers then contact the real ones in turn, performing what we call a man-in-the-middle attack, which is just what it sounds like, sitting between the phones and the real cellphone towers.

This is a fairly sophisticated attack, one made by law enforcement in a highly dubious legal area. That’s why it’s really interesting to see mainstream media cover the topic now.

It’s particularly interesting as law enforcement won’t immediately get identities out of this attack — it will merely read which IMSI numbers were in the area at the time of the man-in-the-middle attack. Some of the time, this could conceivably be translated into people’s actual names, by means of subpoenas or similar to the carriers. A lot of the time, it won’t (think anonymous prepaid SIM cards).

While this attack can be used to track an individual’s movements once you have their IMSI — and has been used for this, notably with the American-made Stingray devices — it’s more alarming that law enforcement is increasingly using the attack to keep a catalog over which people, or at least their phones, are present at a certain type of protest.

Die Zeit’s article also covers countermeasures to the IMSI catcher attack, and mentions that while there are numerous apps that detect IMSI catchers, the better ones can only detect about 90% of those attacks.

We can expect this to escalate in the coming years.

Syndicated Article
This article was previously published at Private Internet Access.

(This is a post from Falkvinge on Liberty, obtained via RSS at this feed.)

Source: 
Rick Falkvinge

Dear friends of this aggregator

  • Yes, I intentionally removed Newsbud from the aggregator on Mar 22.
  • Newsbud did not block the aggregator, although their editor blocked me on twitter after a comment I made to her
  • As far as I know, the only site that blocks this aggregator is Global Research. I have no idea why!!
  • Please stop recommending Newsbud and Global Research to be added to the aggregator.

Support this site

News Sources

Source Items
WWI Hidden History 50
Grayzone Project 111
Pass Blue 175
Dilyana Gaytandzhieva 14
John Pilger 416
The Real News 367
Scrutinised Minds 29
Need To Know News 2383
FEE 4435
Marine Le Pen 320
Francois Asselineau 25
Opassande 53
HAX on 5July 220
Henrik Alexandersson 839
Mohamed Omar 354
Professors Blog 10
Arg Blatte Talar 40
Angry Foreigner 18
Fritte Fritzson 12
Teologiska rummet 32
Filosofiska rummet 103
Vetenskapsradion Historia 151
Snedtänkt (Kalle Lind) 213
Les Crises 2632
Richard Falk 156
Ian Sinclair 100
SpinWatch 59
Counter Currents 8703
Kafila 427
Gail Malone 36
Transnational Foundation 221
Rick Falkvinge 94
The Duran 9438
Vanessa Beeley 93
Nina Kouprianova 9
MintPress 5555
Paul Craig Roberts 1643
News Junkie Post 58
Nomi Prins 27
Kurt Nimmo 191
Strategic Culture 4673
Sir Ken Robinson 20
Stephan Kinsella 92
Liberty Blitzkrieg 841
Sami Bedouin 64
Consortium News 2552
21 Century Wire 3456
Burning Blogger 324
Stephen Gowans 85
David D. Friedman 150
Anarchist Standard 16
The BRICS Post 1506
Tom Dispatch 499
Levant Report 18
The Saker 4127
The Barnes Review 516
John Friend 449
Psyche Truth 150
Jonathan Cook 145
New Eastern Outlook 3774
School Sucks Project 1767
Giza Death Star 1844
Andrew Gavin Marshall 15
Red Ice Radio 606
GMWatch 2189
Robert Faurisson 150
Espionage History Archive 34
Jay's Analysis 918
Le 4ème singe 90
Jacob Cohen 206
Agora Vox 14697
Cercle Des Volontaires 430
Panamza 2093
Fairewinds 115
Project Censored 926
Spy Culture 495
Conspiracy Archive 75
Crystal Clark 11
Timothy Kelly 551
PINAC 1482
The Conscious Resistance 798
Independent Science News 75
The Anti Media 6558
Positive News 820
Brandon Martinez 30
Steven Chovanec 61
Lionel 290
The Mind renewed 439
Natural Society 2619
Yanis Varoufakis 958
Tragedy & Hope 122
Dr. Tim Ball 114
Web of Debt 141
Porkins Policy Review 407
Conspiracy Watch 174
Eva Bartlett 590
Libyan War Truth 321
DeadLine Live 1909
Kevin Ryan 62
BSNEWS 2059
Aaron Franz 224
Traces of Reality 166
Revelations Radio News 121
Dr. Bruce Levine 142
Peter B Collins 1528
Faux Capitalism 205
Dissident Voice 10471
Climate Audit 222
Donna Laframboise 422
Judith Curry 1115
Geneva Business Insider 40
Media Monarchy 2299
Syria Report 78
Human Rights Investigation 91
Intifada (Voice of Palestine) 1685
Down With Tyranny 11506
Laura Wells Solutions 43
Video Rebel's Blog 429
Revisionist Review 485
Aletho News 19885
ضد العولمة 27
Penny for your thoughts 2939
Northerntruthseeker 2319
كساريات 37
Color Revolutions and Geopolitics 27
Stop Nato 4700
AntiWar.com Blog 2987
AntiWar.com Original Content 6771
Corbett Report 2285
Stop Imperialism 491
Land Destroyer 1172
Webster Tarpley Website 1079

Compiled Feeds

Public Lists

Title Visibility
Funny Public