The lockscreen on Elephone P9000 devices (running Android 6.0) allows physically proximate attackers to bypass a wrong-PIN lockout feature by pressing backspace after each PIN guess.
www.reddit.com/r/netsec/comments/6kajkc/elephone_p9000_lock_screen_lockout_bypass_with/
www.security.nl/posting/522081/Schermvergrendeling+Elephone+P9000+door+lek+te+omzeilen
www.trustwave.com/Resources/Security-Advisories/Advisories/TWSL2017-011/?fid=9707
www.trustwave.com/Resources/SpiderLabs-Blog/Elephone-P9000-Lock-Screen-Lockout-Bypass/?page=1&year=0&month=0
www.youtube.com/watch?v=dwyzonP2eZw