Another option is the BAM implementation which seems to allow flashing over CANBus when put into BAM mode:
https://www.st.com/resource/en/data_bri ... lasher.pdf
Watched this great vid of an E41 tear down:
https://www.youtube.com/watch?v=_SCJzzQckCA
Attempts to attack the BAM, which is locked with a different password to default.
So... one would 'assume' the T87a is doing the same. But never a good thing to assume.
Again, attacking via a recovery mode may hold the answers
Dayum, he managed to get into a locked jtag with glitching:
https://eprint.iacr.org/2020/937.pdf
In one of the videos, I believe he described each ecu having a custom password from what he saw in power analysis. So even finding one doesnt mean it works for them all.
I dont believe his documents explicitly state if it is the same or not, but having to do that on every device to rip out the private password to gain access, then modify the boot code.. seems pretty incredible??
Starting to feel more likely towards a recovery state being taken advantage of to upload custom code maybe?