題目連結

https://learn.cylabacademy.org/library/764

題目解法

  1. 輸入 ssh 指令以及密碼來 clone 下專案到本地。

  2. 查看 README.md 內容，得知要使用使用者名稱 root、電子郵件 root@picoctf 來推送 flag.txt 到遠端。

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    $ cat README.md
# MyGit

### If you want the flag, make sure to push the flag!

Only flag.txt pushed by ```root:root@picoctf``` will be updated with the flag.

GOOD LUCK!

  3. 使用 git config 來設定使用者名稱和電子郵件

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    $ git config --local  user.name "root"
$ git config --local  user.email "root@picoctf"

    正常設定時會使用 global 參數，不過這次設定僅套用在此專案，因此使用 local 參數。

  4. 新增 flag.txt

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    touch flag.txt

  5. 新增 commit 並推送到遠端，再推送到遠端時即可得到 flag。

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    $ git add flag.txt
$ git commit -m "feat: add flag.txt"
$ git push

    推送後的內容

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    $ git push
git@foggy-cliff.picoctf.net's password: 
Enumerating objects: 4, done.
Counting objects: 100% (4/4), done.
Delta compression using up to 2 threads
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 273 bytes | 273.00 KiB/s, done.
Total 3 (delta 0), reused 0 (delta 0), pack-reused 0
remote: Author matched and flag.txt found in commit...
remote: Congratulations! You have successfully impersonated the root user
remote: Here's your flag: picoCTF{1mp-----------------------3df}
To ssh://foggy-cliff.picoctf.net:58441/git/challenge.git
    1f391cc..ff4ce9c  master -> master