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Earlier quoted context omitted.
They don't so much backdoor the keying as that they have 4 different cipher profiles, and the one approved for global rather than European use (TEA1) compresses the key from 80 to 32 bits. It's essentially a surreptitious version of what the US did in the 1990s with "export ciphers".
Which makes me question describing this as a "deliberate backdoor."
Earlier quoted context omitted.
They don't so much backdoor the keying as that they have 4 different cipher profiles, and the one approved for global rather than European use (TEA1) compresses the key from 80 to 32 bits. It's essentially a surreptitious version of what the US did in the 1990s with "export ciphers".
Which makes me question describing this as a "deliberate backdoor."
How's that not a backdoor?
The newsworthy item here is that this is an intentional backdoor. The wikipedia pages list the specific uses per country and department. https://en.wikipedia.org/wiki/Terrestrial_Trunked_Radio#Usag...
Do you remember when cryptography export was controlled? It was implemented by limiting key size to certain number of (effective) bits (of security). This suite is just a victim of that law, as it is a 1990s design.
Sounds like they took the "roll your own and don't tell anyone how it works" approach. Security by obscurity is never security. History has shown that the open encryption standards are the most secure.
It's more of intentionally reducing the keyspace when generating keys. You can use weakly generated keys with industry-standard encryption algorithms. When your 4096-bit key is only 32 bits, it doesn't matter how well-trusted the algorithm is.
> The vulnerabilities were discovered during the course of 2020, and were reported to the NCSC in the Netherlands in December of that year. It was decided to hold off public disclosure until July 2023, to give emergency services and equipment suppliers the ability to patch the equipment. Interesting discussion about responsible disclosure. It seems a strange belief that you can tell all the radio operators about the…
> It seems a strange belief that you can tell all the radio operators about the vulnerability without also telling exploiters I suspect that there was an update (or replacement) to the radios that was generally described as an ordinary update / maintenance.
Should the vendor be allowed to continue to sell models they know are compromised while their competition loses those contracts? Shouldn't there be some consequence for such fraud?
What exactly were TETRA radios used for? I assume they were government/infra related, but then I don't understand why they'd need to backdoor the keying
Sounds like they took the "roll your own and don't tell anyone how it works" approach. Security by obscurity is never security. History has shown that the open encryption standards are the most secure.
It's more of intentionally reducing the keyspace when generating keys. You can use weakly generated keys with industry-standard encryption algorithms. When your 4096-bit key is only 32 bits, it doesn't matter how well-trusted the algorithm is.
The newsworthy item here is that this is an intentional backdoor. The wikipedia pages list the specific uses per country and department. https://en.wikipedia.org/wiki/Terrestrial_Trunked_Radio#Usag...
Do you remember when cryptography export was controlled? It was implemented by limiting key size to certain number of (effective) bits (of security). This suite is just a victim of that law, as it is a 1990s design.
> Two of the vulnerabilities are deemed critical. One of them appears to be an intentional backdoor [...] Reading the contents of a firmware upgrade is not trivial though, as it is heavily encrypted and relies on a Trusted Execution Environment (TEE), embedded in the core processor of the radio.* I don't know whether the backdoor allegation is correct, but unfortunately we should treat opaque ostensible security with…