{"categories":["Security"],"blog_url":"https://blog.hamayanhamayan.com/","image_url":null,"html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fblog.hamayanhamayan.com%2Fentry%2F2025%2F03%2F10%2F093739\" title=\"KalmarCTF 2025 Writeup - \u306f\u307e\u3084\u3093\u306f\u307e\u3084\u3093\u306f\u307e\u3084\u3093\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","provider_url":"https://hatena.blog","author_url":"https://blog.hatena.ne.jp/hamayanhamayan/","author_name":"hamayanhamayan","height":"190","blog_title":"\u306f\u307e\u3084\u3093\u306f\u307e\u3084\u3093\u306f\u307e\u3084\u3093","version":"1.0","width":"100%","type":"rich","published":"2025-03-10 09:37:39","url":"https://blog.hamayanhamayan.com/entry/2025/03/10/093739","provider_name":"Hatena Blog","description":"[cry] Very Serious Cryptography [cry] basic sums [cry] Not-so-complex multiplication [cry] Very Serious Cryptography \u4ee5\u4e0b\u306e\u3088\u3046\u306aAES-CBC\u3067\u5fa9\u53f7\u5316\u3092\u3059\u308b\u30b9\u30af\u30ea\u30d7\u30c8\u304c\u4e0e\u3048\u3089\u308c\u308b\u3002 from Crypto.Cipher import AES from Crypto.Util.Padding import pad import os with open(\"flag.txt\", \"rb\") as f: flag = f.read() key = os.urandom(16) # E\u2026","title":"KalmarCTF 2025 Writeup"}