If a criminal gets his hands on the device, they can flash malicious code using custom recoveries such as TWRP even when the bootloader is locked, gaining unrestricted access to everything on the phone. Some testing by OnePlus reveals that the Indian variants of the OnePlus 6 were found to be unstable post the update.
As with most OxygenOS updates, the update to OxygenOS 5.1.7 is rolling out incrementally.
OnePlus 6 starts getting OxygenOS 5.1.7 with bootloader security fix and some new features as well.
Renowned cybersecurity researcher Jason Donenfeld of Edge Security discovered a huge flaw in the OnePlus 6's bootloader. It is also coming with all the features of the v5.1.7. The company further said the OxygenOS 5.1.7 update won't be officially available in India.
OnePlus has confirmed the 5.1.6 update was only pulled for India region, after receiving reportsrelated to stability issues being faced by users there. OnePlus has announced that because of a problem with the previous update (OxygenOS 5.1.6) in India, they will receive OxygenOS 5.1.8 next week, which contains everything from 5.1.6, 5.1.7, and a bugfix for what was causing the instability issues.
Your phone is now updated.
The update is slowly rolling out in all the countries, but it will take some time to reach your smartphone. With such a low-level update as this as well, installing a new bootloader, it might be in your best interest to wait and see if any problems arise for other people first.