题目

GO_Re

WP

代码比较混乱，细看之后找到

image-20220911211958324

加密函数，猜测v1为是输入的值

经过加密之后与v11进行比较

分析加密函数

[image-20220911211952017

调试得到v27

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V27=[243,79,85,235,242,11,136,210,70,121,193,114,95,140,200,114,59,213,194,165,130,41,234,220,20,176,3,159,72,73,88,84]

V11= [0x9f,0x29,0x32,0x8a,0xc3,0x70,0xbc,0xea,0x20,0x40,0xf1,0x17,0x69,0xe8,0xfd,0x40,0x3,0xe6,0xa3,0x97,0xb7,0x1e,0xd3,0xbf,0x24,0x83,0x32,0xab,0x79,0x28,0x25,0x37]

多次尝试之后发现需要两个字节一起两两交换输出flag

脚本如下：

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v27=[243,79,85,235,242,11,136,210,70,121,193,114,95,140,200,114,59,213,194,165,130,41,234,220,20,176,3,159,72,73,88,84]
 v11= [0x9f,0x29,0x32,0x8a,0xc3,0x70,0xbc,0xea,0x20,0x40,0xf1,0x17,0x69,0xe8,0xfd,0x40,0x3,0xe6,0xa3,0x97,0xb7,0x1e,0xd3,0xbf,0x24,0x83,0x32,0xab,0x79,0x28,0x25,0x37]
 flag=''
 for i in range(len(v11)):
   v11[i]^=v27[i]
 for i in range(0,len(v11),2):
   t=v11[i]
   v11[i]=v11[i+1]
   v11[i+1]=t
 for i in range(len(v11)):
   flag+=chr(v11[i])
 print(flag)

# flag{1849fe0d625382a75c93041a1c}