Tim Ward ⭐🇪🇺🔶 #FBPE
@TimWardCam@c.im replied  ·  activity timestamp 4 weeks ago
@evacide Once Upon A Time in the 2G days I worked on software that would, amongst various other interesting things, catch IMSIs. This was, I was told, destined for use by foreign security services abroad ... I didn't ask any further questions. For my own testing I put serious attenuators on the antenna sockets and checked that you could barely receive the signal in the street outside my house (and I set it to an Australian MCC/MNC so that no passing Brits' phones would register).

Imagine my horror when I got a support request: "the attached logs don't look right to us - can you tell us what's going on please?" with the footnote "this was from field testing in a shopping centre in Slough."
Simply Simon
@Salty@mastodon.nz replied  ·  activity timestamp 4 weeks ago
@evacide He says he saw bursts of requests for devices to send their IMSI, but although he (separately) mentions that there is a 2G-downgrade attack he does not say that he noticed this attack in this context.

In 3G+ standards the network must authenticate back to the SIM, a feature specifically designed to make this attack much more difficult. Have US carriers just given up the crown jewels crypto keys to their networks?

Note that network operations that involve requesting IMSI from the device are a legitimate part of the operation of the network. Bursts of authentication-related signalling might simply be a symptom of a locally congested site.
Simply Simon
@Salty@mastodon.nz replied  ·  activity timestamp 4 weeks ago
@evacide Indeed. Of course I would never say *never* but the only time we have for sure experienced a false base station attack here in NZ it was 100% accomplished using 2G downgrade. Unfortunately we can't get handset vendors to disable 2G in firmware because one of our competitors still runs a 2G network and by regulation it must be possible to make emergency calls on any transmitting network ... so ... yeah, we all remain vulnerable to that.
GhostOnTheHalfShell
@GhostOnTheHalfShell@masto.ai replied  ·  activity timestamp 4 weeks ago
@evacide

I long for the day of a simple digital camera.

There is just too much to telemetry. It doesn’t help that Ripple (the company) and Horowitz have donated the money to police departments for surveillance drones and an operation center.

We don’t need the world’s wealthiest men provisioning police forces. It should be seen as a very bad optics.

If only because crypto is so heavily enmeshed with international crime and we’re talking things like human trafficking.