每日刷题|每日刷题记录1

Preface There were some wrong in my previous way of learning.
It’s difficult to consolidate knowledge only by learning knowledge without practice.
So I decide to solve some ctf-subject to consolidate my konwledge.
Why I using English to write this project?
It’s easily to find the reason.
MISC Title : something_in_image
Source : XCTF
File : click here
The file-name is “badimage”,so drop it into 010editor.
Obvious, so much zero ,and only a little informations are normal.
每日刷题|每日刷题记录1
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每日刷题|每日刷题记录1
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Look up “flag”:
It’s easy ,but i want to know hows it work in the real way;
每日刷题|每日刷题记录1
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Look carefully you can find the RAR’s file-header.
Rename the suffix(后缀名) to RAR ,get these files:
每日刷题|每日刷题记录1
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TODO :
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Nothing get ,but i solve it .
RE Title : Hello, CTF
Source : XCTF
File : click me
Hint : 菜鸡发现Flag似乎并不一定是明文比较的
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Drop in IDA:
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Combined with hint , is compare with the encryoted text .
In addtion, the string is HEX ,decrypt result is “CrackMeJustForFun
It’s very much like flag.
flag get!!
CRYPTO Title : flag_in_your_hand
source : XCTF
File : click me
It’s a website :
每日刷题|每日刷题记录1
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Open the js file with vs ,find this string:
每日刷题|每日刷题记录1
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Intuition tells me this is Base64 encrypto , because it’s the same as encrypted tables.
the first part is encrypto by ASCII tables.
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When the number == 3 , the ascii is right ,so the right num is:
[115,101,99,117,114,105,116,121,45,120,98,117]
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Enter it to the website:
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【每日刷题|每日刷题记录1】falg get!!!

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