This is a collection of all challenges (and writeups) in HKCERT CTF 2021
| ID | Chinese name | Name | Score | Solves | Tags (Categories) |
|---|---|---|---|---|---|
| 1 | 玩咗先至瞓 | Sanity Check | 50 | 234 | #☆☆☆☆☆ |
| 2 | Freedom | Cipher Mode Picker | 100 | 21 | #crypto #★☆☆☆☆ |
| 4 | 所有遺失的東西 | All Missing | 150 | 27 | #pwn #★☆☆☆☆ |
| 5 | 留下來的人 | The Remaining One | 300 | 4 | #pwn #misc #★★★☆☆ |
| 6 | 今天我不想做嘢 | Let's Chill | 450 | 4 | #reverse #misc #★★★★☆ |
| 7 | 集合吧！地球保衛隊 | Sratslla SEA | 450 | 2 | #crypto #★★★★☆ |
| 10 | Ophiuchus | Ophiuchus | 500 | 2 | #web #★★★★★ |
| 11 | 無聲浪 | The Wave of Us | 50 | 152 | #forensics #☆☆☆☆☆ |
| 12 | 深夜浪漫 1 | babyURIi | 200 | 4 | #pwn #web #★★☆☆☆ |
| 15 | 幫緊你！幫緊你！ | Flag Checker™ | 250 | 3 | #pwn #★★☆☆☆ |
| 17 | 最難行的路 | The Hardest Path | 300 | 9 | #reverse #misc #★★★☆☆ |
| 20 | 開燈．熄燈 (熄燈版) | Jail of Blind | 300 | 4 | #pwn #★★★☆☆ |
| 22 | 小諧星 | A Joke Cipher | 50 | 88 | #crypto #☆☆☆☆☆ |
| 23 | 郵差叔叔送信純熟迅速送出 1 | Jack Botnet Service 1 | 300 | 12 | #forensics #★★★☆☆ |
| 24 | 郵差叔叔送信純熟迅速送出 2 | Jack Botnet Service 2 | 300 | 8 | #forensics #★★★☆☆ |
| 28 | 想改寫的事 | To Modify the Past | 50 | 54 | #pwn #☆☆☆☆☆ |
| 29 | 告別式 | Cool Down | 200 | 10 | #pwn #★★☆☆☆ |
| 30 | 世上唯一雙細胞 1 | Fortune Cookie 1 | 250 | 4 | #pwn #★★☆☆☆ |
| 31 | 世上唯一雙細胞 2 | Fortune Cookie 2 | 350 | 3 | #pwn #★★★☆☆ |
| 32 | 薛丁格的盒子 | Unobserved Box | 250 | 6 | #pwn #reverse #★★☆☆☆ |
| 35 | 千世書 | Mastermind | 500 | 0 | #pwn #★★★★★ |
| 36 | 逐步拾回自己 | Step by Step | 100 | 68 | #reverse #misc #★☆☆☆☆ |
| 37 | 暈暈陀陀 1 | CTF Tuning Master (Read) | 150 | 15 | #web #misc #★☆☆☆☆ |
| 38 | 點點心 | Steamed Meatball | 150 | 7 | #misc #★☆☆☆☆ |
| 39 | 選擇困難 | Difficult Choice | 400 | 5 | #forensics #★★★★☆ |
| 40 | 純孩兒 | babyXSS | 100 | 37 | #web #★☆☆☆☆ |
| 41 | 消失的人 | The Disappeared | 200 | 51 | #forensics #★★☆☆☆ |
| 43 | 理性與任性之間 | Shuffle | 50 | 60 | #reverse #☆☆☆☆☆ |
| 44 | 哥本哈根的另一個我 | Another VM in København | 300 | 2 | #reverse #★★★☆☆ |
| 45 | 一知半解 | Half-truth VM | 250 | 2 | #crypto #reverse #★★☆☆☆ |
| 46 | 要做更壞的事 | Make it worse VM | 500 | 0 | #pwn #reverse #★★★★★ |
| 49 | 漫漫碎 | Scattered | 100 | 16 | #reverse #★☆☆☆☆ |
| 51 | Old Fashioned | ↑←↓↑x | 250 | 11 | #reverse #★★☆☆☆ |
| 53 | 無門 | No Door 1 | 100 | 6 | #forensics #★☆☆☆☆ |
| 54 | 幻象 | No Door 2 | 200 | 14 | #forensics #★★☆☆☆ |
| 55 | 塵 | Positron | 400 | 3 | #crypto #pwn #reverse #web #misc #★★★★☆ |
| 56 | 因講了出來 | Because I Said It | 150 | 76 | #web #★☆☆☆☆ |
| 57 | 長話短說 | Key Backup Service 1 | 150 | 6 | #crypto #★☆☆☆☆ |
| 58 | Braceless | Key Backup Service 2 | 350 | 5 | #crypto #★★★☆☆ |
| 59 | 返鄕下耕田啦你 | easyheap | 250 | 5 | #pwn #★★☆☆☆ |
| 61 | 倒數 | babyre | 450 | 3 | #reverse #★★★★☆ |
| 62 | 角落生物 1 | Squirrel Community 1 | 50 | 176 | #web #☆☆☆☆☆ |
| 63 | 回到12歲 | scratch-tic-tac-toe | 200 | 86 | #misc #★★☆☆☆ |
| 64 | 荊棘海 | The Wilderness | 100 | 39 | #web #★☆☆☆☆ |
| 67 | 約定的夢幻島 | Sign In Please, Again | 500 | 2 | #crypto #★★★★★ |
| 70 | 樂園 | JQ Playground | 200 | 15 | #web #★★☆☆☆ |
| 72 | 中二病人 | A Junior Mathematician | 350 | 3 | #reverse #★★★☆☆ |
| 74 | 時間的囚犯 | Timebomb | 100 | 16 | #reverse #★☆☆☆☆ |
| 79 | FreeRider | Tenet: The Plagarism | 350 | 4 | #crypto #★★★☆☆ |
| 98 | 網絡安全隱患 | Infant Browser | 50 | 52 | #pwn #web #☆☆☆☆☆ |
| 111 | 神奇的糊塗魔藥 | Potion of Ciphermath | 450 | 1 | #crypto #misc #★★★★☆ |
| 123 | 差一些什麼? | babyUXSS | 100 | 7 | #web #★☆☆☆☆ |
| 60944 | 係咁先啦 | Feedback | 50 | 169 | #☆☆☆☆☆ |
| 6825524 | 深夜浪漫 2 | Return of babyURIi | 350 | 3 | #web #★★★☆☆ |
| 24397312 | 角落生物 2 | Squirrel Community 2 | 250 | 2 | #web #★★☆☆☆ |
| 33330996 | 暈暈陀陀 2 | CTF Tuning Master (Execute) | 300 | 3 | #web #★★★☆☆ |