CVE-2026-10678 NULL-pointer / out-of-bounds write in Zephyr MCTP I2C+GPIO target binding driven by an unauthenticated I2C controller

The MCTP-over-I2C+GPIO target binding in Zephyr subsys/pmci/mctp/mctpi2cgpiotarget.c processes pseudo-register writes from an I2C bus master byte-by-byte in mctpi2cgpiotargetwritereceived without validating the order or the receive buffer. In the affected versions the MCTPI2CGPIORXMSGADDR data...