Feeds

$25 toy radio used to knock out feds

Thousand dollar radio can track them too

The essential guide to IT transformation

Researchers looking at the security of the US Project 25 radio network, used by federal agents and local police, have discovered that it's easily jammed, and almost as easily compromised.

During a two-year study, the researchers from the University of Pennsylvania found that encryption on the police network was routinely switched off, but also demonstrated how a $25 toy could be reprogrammed to knock out radio transmissions – even being able to exclude specific users or subnets – and how a more-expensive option could track a specific user.

Pink, toy, radio

The GirlTECH IMme: Giving girls access to technology was always going to be dangerous

Project 25 is the US equivalent to TETRA, a standard radio platform for local and federal police to communicate in groups during operations. But unlike TETRA, which is deployed in green-field radio spectrum, P25 had to be compatible with the existing analogue systems and is thus squeezed into a fixed 12.5kHz channel, though that's not the only thing making it vulnerable.

The digital system uses fixed-length packets, optionally encrypted using a symmetric key (distributed to handsets manually or over the air). The first problem is that key distribution doesn't always work, so the team found users frequently get cut out and have to ask the rest of the group to switch off encryption for the duration of the operation. Individual users can also, inadvertently, switch off their own encryption without other users being alert enough to notice.

But even when encryption is being used properly, the packet header is sent in the clear, allowing a well-timed jammer to knock out the encryption keys (thus forcing a team to switch off encryption), or knock out transmissions from a specific user. Worse still, a corrupted message addressed to a user prompts their radio to respond with a resent request, allowing an attacker to triangulate the attacked user's location.

The ease with which the radios can be knocked out is alarming, though the researchers did have to spend some months (two years in total) monitoring sections of the 2000 frequencies available to the police to identify bands where interesting conversations were taking place. Having done that, they were able to hear names and locations of criminals under investigation, details of surveillance operations, and plans for forthcoming arrests.

Fortunately, and despite media portrayals, few criminal organisations are quite organised enough to create such an information brokerage.

The researchers' paper (16-page PDF/9.2MB, nicely written but complicated) does have practical advice for users of P25 – reprogramming handsets to make switching off encryption less obvious, and reminding users when it has been switched off – but they conclude that fundamentally the P25 system wasn't designed with a properly layered security model, and that this will always leave it more vulnerable than it should be. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
'Stop dissing Google or quit': OK, I quit, says Code Club co-founder
And now a message from our sponsors: 'STFU or else'
Ex US cybersecurity czar guilty in child sex abuse website case
Health and Human Services IT security chief headed online to share vile images
Don't even THINK about copyright violation, says Indian state
Pre-emptive arrest for pirates in Karnataka
The police are WRONG: Watching YouTube videos is NOT illegal
And our man Corfield is pretty bloody cross about it
Felony charges? Harsh! Alleged Anon hackers plead guilty to misdemeanours
US judge questions harsh sentence sought by prosecutors
Oz biz regulator discovers shared servers in EPIC FACEPALM
'Not aware' that one IP can hold more than one Website
Apple tried to get a ban on Galaxy, judge said: NO, NO, NO
Judge Koh refuses Samsung ban for the third time
prev story

Whitepapers

Top 10 endpoint backup mistakes
Avoid the ten endpoint backup mistakes to ensure that your critical corporate data is protected and end user productivity is improved.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Backing up distributed data
Eliminating the redundant use of bandwidth and storage capacity and application consolidation in the modern data center.
The essential guide to IT transformation
ServiceNow discusses three IT transformations that can help CIOs automate IT services to transform IT and the enterprise
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.