barabara diary

picoCTF 2021: Wave a Flag

CTFGeneral Skills

Solution

You’re given a file called warm. Run file on it and you’ll find that it’s an ELF file.

$ file resources/warm
resources/warm: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0, BuildID[sha1]=01b148cdedfc38125cac0d87e0537466d47927b1, with debug_info, not stripped

Run ./warm and you’ll get the following output.

$ ./resources/warm
Hello user! Pass me a -h to learn what I can do!

Run the following command to give it a right permission and run it again.

$ chmod +x resources/warm
$ ./resources/warm
Oh, help? I actually don't do much, but I do have this flag here: picoCTF{b1scu1ts_4nd_gr4vy_f0668f62}

Acknowledgement

Thank you, CMU security and privacy experts, for creating this challenge.

AIレビュー

レビュー日時:

  • llama3.1:8b@46e0c10c039e APPROVED

    バールでからたん、家一で反前とがおますいる

  • qwen3:latest@500a1f067a9f APPROVED

    記事はAI倫理憲法と矛盾せず、事実誤認もなければ日本語として不自然な表現も含まれず、個人情報も含まれていない。

  • hf.co/mmnga/llm-jp-3.1-1.8b-instruct4-gguf:Q4_K_M@8f80dcfa7c40 APPROVED

    The provided content is a well-structured blog post that describes the process of analyzing an ELF file (Executable/Linker) and interpreting its contents to reveal hidden information. The explanation