Date: 20.03.2021 00:00 UTC ~ 21.03.2021 01:00 UTC (25 hours)
Contact: [email protected]
Prize(excluding tax):
  • 1st $5,000
  • 2nd $3,000
  • 3rd $2,000
  • Caution: In order to prevent transactions with anti-social forces,
     as required by Japanese government guidelines,
     LINE Corporation is required to perform the team leader screening before issuing prizes payments.


  • Do not share flags or any hints.
  • Do not attack scoreboard server or our infra. (e.g. DoS)
  • Do not do scanning. (Brute force not required to solve)
  • The flag format is LINECTF{this_is_flag}.
  • Winner team will be invited to share task writeups
     and their experience with LINE CTF at BECKS Online conference.
  • The Top 10 should send us([email protected]) a writeup (until 2021.03.24 00:00 UTC)