Integer overflow in app/aboot/aboot.c in the Qualcomm bootloader in Android before 2016-08-05 on Nexus 5, 5X, 6P, and 7 (2013) devices allows attackers to gain privileges via a crafted header field in a boot image, aka Android internal bug 27917291 and Qualcomm internal bug CR945164.
https://source.codeaurora.org/quic/la/kernel/lk/commit/?id=030371d45a9dcda4d0cc3c76647e753a1cc1b782