alt Hacker NewsAFAIK every popular Android phone uses a qualcomm modem chip with a separate OS that has complete access to ram. NSA most certainly has a backdoor there and such complete access to any Android phone. This was common knowledge after the Snowden stuff. I don't think this has changed at all since. Only few niche phones (pinephone) separate these systems or have a hardware switch to disable the cellular system.
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> NSA most certainly has a backdoor there and such complete access to any Android phone.
Citation needed?
> This was common knowledge after the Snowden stuff.
Not to me, it isn't? As far as I'm aware, most of the Snowden stuff were centered around PRISM, which allowed widescale wiretapping of internet backbone, as well as agreements with big cloud providers to allow tapping into their data.
I haven't seen anything indicating that there was widespread compromise of personal computing devices at such a deep level of the root of trust. I haven't seen any indication that the NSA has a backdoor in the earlyboot CPU of any device, whether that is the Qualcomm boot processor, the Intel Management Engine or the AMD Platform Security Processor (which all have similar capabilities and hidden firmware).
If I missed anything/have links to research into these backdoors, I'd like to see them!
>I don't think this has changed at all since.
There is common knowledge to suggest that it is not the case (or maybe is no longer the case):
>Mainstream smartphones do not provide DMA access from the baseband to the application processor's memory... Yes, getting baseband access then lets you monitor regular voice and SMS comms. But no, it does not instantly compromise the AP so using the Signal app would still be secure. https://news.ycombinator.com/item?id=10906488
>Apple mitigates baseband processor vulnerabilities by putting it behind what's essentially an IOMMU. https://news.ycombinator.com/item?id=29440154
>This is false FUD that keeps being repeated. It's not true. No iPhone ever has had a baseband with DMA access to my knowledge, and modern Qualcomm devices have advanced IOMMU systems to firewall away the baseband from the rest of system memory. I'm sure some phones somewhere existed where the baseband was privileged, but it's not the norm. https://news.ycombinator.com/item?id=30393283
>Connecting a cellular radio via USB provides far less isolation than the approach of a tiny kernel driver connected to an IOMMU isolated cellular radio on mainstream devices. USB has immense complexity and attack surface, especially with a standard Linux kernel configuration. Forensic data extraction companies mostly haven't bothered using attack vectors other than USB due to it being such a weak point. Many of the things people claim about cellular radios in mainstream smartphones are largely not true and they're missing that other radios are implemented in a very comparable way. https://news.ycombinator.com/item?id=46841004