--- title: "sonw (@s-0wn) | Hashnode" description: "sonw (@s-0wn) writes on Hashnode. Read their latest articles and follow their work." url: "https://hashnode.com/@s-0wn" --- @s-0wn # sonw @s-0wn · Joined May 2025 ### [(english ver.) \[HTB CTF Nightfall 2026 - Blockchain Track\] Impossible: Hard Level](https://s-0wn.hashnode.dev/english-ver-htb-ctf-nightfall-2026-blockchain-track-impossible-hard-level?utm_source=hashnode&utm_medium=feed) The challenge tells us that there is an on-chain reserve containing funds, but it is locked. Only an authorized relay user can withdraw from it, and the player is obviously not one of those users :v. 6 min read · [s-0wn.hashnode.dev](https://s-0wn.hashnode.dev/english-ver-htb-ctf-nightfall-2026-blockchain-track-impossible-hard-level?utm_source=hashnode&utm_medium=feed) [Jul 1](https://hashnode.com/posts/english-ver-htb-ctf-nightfall-2026-blockchain-track-impossible-hard-level/6a44ceaa74ccdd686aac612b) ### [(english ver.) \[HTB CTF Nightfall 2026 - Blockchain Track\] Vivarium: Medium Level](https://s-0wn.hashnode.dev/english-ver-htb-ctf-nightfall-2026-blockchain-track-vivarium-medium-level?utm_source=hashnode&utm_medium=feed) Somehow, I solved this challenge pretty quickly, probably even faster than the easy one, and the reason was rather unusual. The challenge describes VIVARIUM as a private yield vault holding VIVM tok 5 min read · [s-0wn.hashnode.dev](https://s-0wn.hashnode.dev/english-ver-htb-ctf-nightfall-2026-blockchain-track-vivarium-medium-level?utm_source=hashnode&utm_medium=feed) [Jul 1](https://hashnode.com/posts/english-ver-htb-ctf-nightfall-2026-blockchain-track-vivarium-medium-level/6a44cd20c736bd97cc62a289) ### [(english ver.) \[HTB CTF Nightfall 2026 - Blockchain Track\] Grant Registry: Easy Level](https://s-0wn.hashnode.dev/english-ver-htb-ctf-nightfall-2026-blockchain-track-grant-registry-easy-level?utm_source=hashnode&utm_medium=feed) A juicy CTF came into my company room. Unfortunately, I came back late from an outing, so the team had already solved almost all the top Web and Mobile challenges. Luckily, I still have my blockchain 6 min read · [s-0wn.hashnode.dev](https://s-0wn.hashnode.dev/english-ver-htb-ctf-nightfall-2026-blockchain-track-grant-registry-easy-level?utm_source=hashnode&utm_medium=feed) [Jul 1](https://hashnode.com/posts/english-ver-htb-ctf-nightfall-2026-blockchain-track-grant-registry-easy-level/6a44cb6102a4bc82a5ac7233) ### [\[HTB CTF Nightfall 2026 - Blockchain Track\] Impossible: Hard Level](https://s-0wn.hashnode.dev/htb-ctf-nightfall-2026-blockchain-track-impossible-hard-level?utm_source=hashnode&utm_medium=feed) Đề cho biết có một kho tiền trên chain nhưng đang bị khóa, chỉ có user được ủy quyền relay mới rút được, và trong đó không bao gồm người chơi :v. Ngay khi mình check trong smart contract liên quan thì 6 min read · [s-0wn.hashnode.dev](https://s-0wn.hashnode.dev/htb-ctf-nightfall-2026-blockchain-track-impossible-hard-level?utm_source=hashnode&utm_medium=feed) [Jun 1](https://hashnode.com/posts/htb-ctf-nightfall-2026-blockchain-track-impossible-hard-level/6a1d4026d20e8f1b5ce9fd33) ### [\[HTB CTF Nightfall 2026 - Blockchain Track\] Vivarium: Medium Level](https://s-0wn.hashnode.dev/htb-ctf-nightfall-2026-blockchain-track-vivarium-medium-level?utm_source=hashnode&utm_medium=feed) Bài này trộm vía mình làm khá nhanh, có lẽ nhanh hơn cả bài easy, lý do cũng kì kì. Đề bài mô tả VIVARIUM là một private yield vault đang giữ token VIVM, mục tiêu là “drain it to zero”. File phát ch 5 min read · [s-0wn.hashnode.dev](https://s-0wn.hashnode.dev/htb-ctf-nightfall-2026-blockchain-track-vivarium-medium-level?utm_source=hashnode&utm_medium=feed) [Jun 1](https://hashnode.com/posts/htb-ctf-nightfall-2026-blockchain-track-vivarium-medium-level/6a1d383be6ddcdc8ca793c7e)