This repository contains official source code and writeups for challenges from SekaiCTF 2026.
| Name | Author | Difficulty | Solves |
|---|---|---|---|
| PP Farming* | brokenappendix | 1⟡ (Easy) | 444 |
| PP Farming 2* | brokenappendix | 2⟡ (Normal) | 167 |
| Open World* | y4nhu1 | 2⟡ (Normal) | 149 |
| Outer Stellar* | snwo | 4⟡ (Expert) | 130 |
| Name | Author | Difficulty | Solves |
|---|---|---|---|
| oneline6ryp7o | Neobeo | 1⟡ (Easy) | 423 |
| orbital-strike | Water | 3⟡ (Hard) | 89 |
| needLe in a multivariate sekai | sceleri | 5⟡ (Master) | 43 |
| Iihash | sceleri | 5⟡ (Master) | 29 |
| apbq-rsa-iv | Neobeo | 5⟡ (Master) | 11 |
| Name | Author | Difficulty | Solves |
|---|---|---|---|
| ▶ Sanity Check | SekaiCTF | 1⟡ (Easy) | 788 |
| impossible stego | sy1vi3 | 1⟡ (Easy) | 295 |
| Survey | SekaiCTF | 1⟡ (Easy) | 246 |
| (game) Bejeweled | Eana, sahuang | 1⟡ (Easy) | 195 |
| skyblock | es3n1n, Pindos | 1⟡ (Easy) | 153 |
| (game) 6-7 Puzzle Hunt | Neobeo | 2⟡ (Normal) | 362 |
| ufo | krauq | 2⟡ (Normal) | 168 |
| deadgame2 | 探姬 (XCTF) | 2⟡ (Normal) | 137 |
| SekaiID | Marc | 3⟡ (Hard) | 147 |
| (game) Minions in 16k* | mixy1 | 4⟡ (Expert) | 244 |
| pokemon park | sy1vi3 | 5⟡ (Master) | 29 |
| pokemon park revenge | sy1vi3 | 6⟡ (Append) | 27 |
| pwnable document fabricator* | SekaiCTF | 6⟡ (Append) | 0 |
| Name | Author | Difficulty | Solves |
|---|---|---|---|
| ppp | Marc | 1⟡ (Easy) | 243 |
| echo-chamber | unvariant | 3⟡ (Hard) | 6 |
| MTE | Qyn | 4⟡ (Expert) | 9 |
| 3in1* | Qyn | 5⟡ (Master) | 1 |
| Name | Author | Difficulty | Solves |
|---|---|---|---|
| Untitled Encore | sahuang | 2⟡ (Normal) | 238 |
| Chibile | ELJoOker | 3⟡ (Hard) | 79 |
| mikuprotect | es3n1n, bs1337 | 3⟡ (Hard) | 55 |
| nevm* | hexamine | 4⟡ (Expert) | 1 |
| Name | Author | Difficulty | Solves |
|---|---|---|---|
| Migurimental | beluga | 1⟡ (Easy) | 156 |
| <\w+ | claustra01 | 2⟡ (Normal) | 85 |
| EnD | zonkor | 4⟡ (Expert) | 26 |
| Filtered Reality | dimasma0305 | 4⟡ (Expert) | 7 |
Challenges marked with an asterisk (*) were eligible for bounties during the CTF. For certain unsolved challenges, the bounty remained available after the competition concluded:
| Category | Name | Difficulty | Solves | Bounty |
|---|---|---|---|---|
| Binary Exploitation | 3in1 | 5⟡ (Master) | 1 |  $100 |
| Blockchains | PP Farming | 1⟡ (Easy) | 444 | $100 |
| Blockchains | PP Farming 2 | 2⟡ (Normal) | 167 | $100 |
| Blockchains | Open World | 2⟡ (Normal) | 149 | $100 |
| Blockchains | Outer Stellar | 4⟡ (Expert) | 130 | $100 |
| Miscellaneous | (game) Minions in 16k | 4⟡ (Expert) | 244 | $100 |
| Miscellaneous | pwnable document fabricator | 6⟡ (Append) | 0 | $100 |
| Reverse Engineering | nevm | 4⟡ (Expert) | 1 | $100 |
Any program and/or source code in this repository is licensed under the GNU Affero General Public License version 3:
SEKAI CTF 2026 Challenges and Solutions
Copyright (C) 2026 Project SEKAI CTF team and contributorsThis program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License along with this program. If not, see https://www.gnu.org/licenses/.
Any non-code/program content (writeups, READMEs, descriptions) in this repository is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (CC BY-NC-SA 4.0):
SEKAI CTF 2026 Challenges and Solutions by Project SEKAI CTF team and contributors is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.