{"id":1674,"date":"2024-03-08T17:30:33","date_gmt":"2024-03-08T08:30:33","guid":{"rendered":"https:\/\/h4ck.kr\/?p=1674"},"modified":"2024-05-20T13:26:25","modified_gmt":"2024-05-20T04:26:25","slug":"vishwactf-2024-happy-valentines-day","status":"publish","type":"post","link":"https:\/\/h4ck.kr\/?p=1674","title":{"rendered":"VishwaCTF 2024 – Happy Valentine’s Day"},"content":{"rendered":"\n
\"\"<\/figure>\n\n\n\n

DESCRIPTION<\/h2>\n\n\n\n

My girlfriend and I captured our best moments of Valentine’s Day in a portable graphics network. But unfortunately I am not able to open it as I accidentally ended up encrypting it. Can you help me get my memories back?<\/p>\n\n\n\n

Author : Pushkar Deore<\/strong><\/p>\n\n\n\n

FLAG FORMAT:<\/h2>\n\n\n\n

VishwaCTF{}<\/code><\/p>\n\n\n\n

Attachments<\/h2>\n\n\n\n

2\uac00\uc9c0 \ud30c\uc77c\ub4e4\uc774 \uc874\uc7ac\ud55c\ub2e4.<\/p>\n\n\n\n

source.txt – png \uc774\ubbf8\uc9c0 \ud30c\uc77c\uc744 \uc554\ud638\ud654\uc2dc\ud0a4\ub294 python3 \uc2a4\ud06c\ub9bd\ud2b8
enc.txt – \uc554\ud638\ud654\ub41c png \uc774\ubbf8\uc9c0<\/p>\n\n\n\n

source.txt<\/h2>\n\n\n\n
\n
\n
from PIL import Image\nfrom itertools import cycle\n\ndef xor(a, b):\n    return [i^j for i, j in zip(a, cycle(b))]\n\nf = open(\"original.png\", \"rb\").read()\nkey = [f[0], f[1], f[2], f[3], f[4], f[5], f[6], f[7]]\n\nenc = bytearray(xor(f,key))\n\nopen('enc.txt', 'wb').write(enc)<\/pre>\n<\/div>\n<\/div>\n\n\n\n
\uc554\ud638\ud654\ub418\uc9c0 \uc54a\uc740 \uc6d0\ubcf8 \uc774\ubbf8\uc9c0 \ud30c\uc77c\uc5d0\uc11c 8\ubc14\uc774\ud2b8 \uc2dc\uadf8\ub2c8\ucc98 \ud5e4\ub354\uac12\uc73c\ub85c XOR \uc554\ud638\ud654\uc2dc\ud0a4\uace0 \uc788\uc5c8\ub2e4.<\/p>\n\n\n\n
solve.py<\/h2>\n\n\n\n
\n
\n
from PIL import Image\nfrom itertools import cycle\n\ndef xor(a, b):\n    return [i^j for i, j in zip(a, cycle(b))]\n\nenc = open(\"enc.txt\", \"rb\").read()\nkey = [0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A]\ndec = bytearray(xor(enc,key))\n\nopen('enc.txt.png', 'wb').write(dec)<\/pre>\n<\/div>\n<\/div>\n\n\n\n
8\ubc14\uc774\ud2b8 png \uc2dc\uadf8\ub2c8\ucc98 \ud5e4\ub354\uac12\uc740 \uc774\ubbf8 \uc54c\ub824\uc838\uc788\uae30 \ub54c\ubb38\uc5d0, 
\uadf8 \uac12\uc73c\ub85c \ub2e4\uc2dc XOR \uc5f0\uc0b0\uc2dc\ud0a4\uba74 \ub41c\ub2e4. <\/p>\n\n\n\n
FLAG<\/h2>\n\n\n\n
\"\"<\/figure>\n\n\n\n
\"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"
DESCRIPTION My girlfriend and I captured our best moments of Valentine’s Day in a portable graphics network. But unfortunately I am not able to open it as I accidentally ended up encrypting it. Can you help me get my memories back? Author : Pushkar Deore FLAG FORMAT: VishwaCTF{} Attachments 2\uac00\uc9c0 \ud30c\uc77c\ub4e4\uc774 \uc874\uc7ac\ud55c\ub2e4. source.txt – png… \ub354 \ubcf4\uae30 »VishwaCTF 2024 – Happy Valentine’s Day<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"neve_meta_sidebar":"","neve_meta_container":"","neve_meta_enable_content_width":"","neve_meta_content_width":0,"neve_meta_title_alignment":"","neve_meta_author_avatar":"","neve_post_elements_order":"","neve_meta_disable_header":"","neve_meta_disable_footer":"","neve_meta_disable_title":"","footnotes":""},"categories":[19],"tags":[28],"class_list":["post-1674","post","type-post","status-publish","format-standard","hentry","category-ctf-private","tag-cryptography"],"_links":{"self":[{"href":"https:\/\/h4ck.kr\/index.php?rest_route=\/wp\/v2\/posts\/1674","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/h4ck.kr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/h4ck.kr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/h4ck.kr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/h4ck.kr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1674"}],"version-history":[{"count":2,"href":"https:\/\/h4ck.kr\/index.php?rest_route=\/wp\/v2\/posts\/1674\/revisions"}],"predecessor-version":[{"id":1681,"href":"https:\/\/h4ck.kr\/index.php?rest_route=\/wp\/v2\/posts\/1674\/revisions\/1681"}],"wp:attachment":[{"href":"https:\/\/h4ck.kr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1674"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/h4ck.kr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1674"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/h4ck.kr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1674"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}