Yes. The baseband on an iPhone is effectively just a USB peripheral. Did you think Apple spent tens of millions of dollars designing a custom secure enclave processor running a separate operating system unrelated to iOS and just said "fuck it, give the whole system to the baseband vendor"?
"To protect the device from vulnerabilities in network processor firmware, network interfaces including Wi-Fi and baseband have limited access to application processor memory. When USB or SDIO is used to interface with the network processor, the network processor can’t initiate Direct Memory Access (DMA) transactions to the application processor. When PCIe is used, each network processor is on its own isolated PCIe bus. An IOMMU on each PCIe bus limits the network processor’s DMA access to pages of memory containing its network packets or control structures."
It's still a common meme that on modern phones the baseband has full access to whatever it wants. The available evidence (which admittedly is very scant) and common sense suggests that this is not true, not in iPhones or common chipsets used in Android phones.
It may have been true on older phones with simpler system architectures but you're really going to need some new evidence to show the meme still holds true.
available evidence (which admittedly is very scant)
How do you figure? When Apple or Google say 'baseband is constrained from accessing OS memory in the following ways', these aren't unverifiable claims. People would be doing demos at conferences showing malicious basebands thieving your private catpictures.
Mh, from GSM official docs SIM cards are small OSes with yes a limited power, but not that limited, they can officially set various kind of phone options, use speakerphone etc.
Of course that does not automatically means that those systems do exists like fictional echelon project but potentially power is there and know tech also...
