[BUG] Challenge 10 in the linux lab triggered by local file creation

[FrancescoSer]

Describe the bug

When running the linux lab, the flag from challenge 10:

10	Remote Upload	Transfer any file to ctf_challenges to trigger the flag	⭐⭐	File transfer, SCP

can be triggered without using scp, by just creating any file on the file system.
Using scp for transfering a file does not trigger the challenge.

System information:

• OS: Ubuntu 24.04
• Cloud Provider: Azure
• Terraform Version: Terraform v1.16.2
• Cloud CLI Version: az version 2.90.0

To Reproduce
Steps to reproduce the behavior:

scp <filename> <user>@<server_ip:~/<filename>

Expected behavior
Challenge passed and flag shown

Actual behavior
Nothing happens when running scp.
The flag is shown when running vi <any_filename> on the remote machine via SSH.

[github-actions]

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[FrancescoSer]

Unfortunately, I didn't keep the logs from the lab. However, the bug should be easily reproducible.

[madebygps]

Thanks @FrancescoSer for reporting this! 🙏

We reproduced it on an Azure VM. scp does trigger the flag, but only when the file goes into ~/ctf_challenges/ and is a new file. The command in the report sent it to ~/, which isn't watched. That wasn't clear from the instructions, and the hint suggested just creating a file on the VM instead of uploading one.

Fixed in #128, released in v0.1.9:

• The README and verify hint 10 now say to upload a new file with scp, from your own computer, into user@ip:~/ctf_challenges/
• The watcher now shows one banner per upload, instead of several when vim creates temporary files
• Our test suite now checks challenge 10 with a real scp upload

New deployments pick this up automatically. If you have a lab running, run terraform destroy and terraform apply again to get the fix.