Google CTF 2021: Writeup Competition winners

[Google CTF]

Hello,

the following write-ups have been selected as winners of the Google CTF 2021 write-up competition:

• https://jsur.in/posts/2021-07-19-google-ctf-2021-crypto-writeups#h1 (crypto/h1)
• https://gist.github.com/rot256/4eb32fe82aadd34ed0fc43cd14026eb0 (crypto/h1)
• https://susanou.github.io/Writeups/posts/pythia/ (crypto/pythia)
• https://gist.github.com/deut-erium/67742dc11424eb5ff91fe129cf84a7d4 (crypto/pythia)
• https://jsur.in/posts/2021-07-19-google-ctf-2021-crypto-writeups#story (crypto/story)
• https://jsur.in/posts/2021-07-19-google-ctf-2021-crypto-writeups#tiramisu (crypto/tiramisu)
• https://mystiz.hk/posts/2021-07-24-gooogle-ctf/#tonality (crypto/tonality)
• https://github.com/p4-team/ctf/tree/master/2021-07-17-google-ctf/comlink (hw/comlink)
• https://anniequus.com/posts/googlectf-parking/ (hw/parking)
• https://github.com/EmpireCTF/empirectf/blob/62e379696228214e60ff62c221baebaf222f925c/writeups/2021-07-17-Google-CTF/README.md#234-hardware--parking (hw/parking)
• attachment pcivault1.md (hw/pcivault1)
• https://github.com/TheMaccabees/ctf-writeups/blob/master/GoogleCTF2021/ABCARMANDAMD/README.md (misc/ABC ARM AND AMD)
• https://balsn.tw/ctf_writeup/20210717-googlectf2021/#abc-arm-and-amd (misc/ABC ARM AND AMD)
• https://github.com/luker983/google-ctf-2021/blob/main/misc/david-and-the-tree/README.md (misc/david and the tree)
• https://www.proggen.org/doku.php?id=security:ctf:writeup:google:2021:filestore (misc/filestore)
• https://www.cis.upenn.edu/~hanbangw/blog/google-ctf-2021/#icantbelieveitsnotcrypto (misc/ICAN'TBELIEVEIT'SNOTCRYPTO)
• attachment raiders.md (misc/raiders of corruption)
• https://balsn.tw/ctf_writeup/20210717-googlectf2021/#raiders-of-corruption (misc/raiders of corruption)
• https://gist.github.com/mikecat/a580c9c91f54f514beb138c77e1675e2 (pwn/compression)
• https://mem2019.github.io/jekyll/update/2021/07/19/GCTF2021-eBPF.html (pwn/ebpf)
• https://ret2.life/posts/Google-CTF-2021/ and https://trungnguyen1909.github.io/blog/post/GGCTF21 (pwn/fullchain)
• https://balsn.tw/ctf_writeup/20210717-googlectf2021/#fullchain (pwn/fullchain)
• https://github.com/EmpireCTF/empirectf/blob/62e379696228214e60ff62c221baebaf222f925c/writeups/2021-07-17-Google-CTF/README.md#203-pwn--memsafety (pwn/memsafety)
• https://github.com/Super-Guesser/ctf/blob/master/2021/google-ctf/pwn/tridroid/README.md (pwn/tridroid)
• https://fineas.github.io/FeDEX/post/tridroid.html (pwn/tridroid)
• https://balsn.tw/ctf_writeup/20210717-googlectf2021/#adspam (re/adspam)
• https://www.cis.upenn.edu/~hanbangw/blog/google-ctf-2021/#cpp (re/cpp)
• https://gist.github.com/beepboop271/3add028fd10870eba8e75d7c694b77d3 (re/cpp)
• https://github.com/cscosu/ctf-writeups/blob/master/2021/google_ctf/hexagon/README.md (re/hexagon)
• https://balsn.tw/ctf_writeup/20210717-googlectf2021/#polymorph (re/polymorph)
• https://lkmidas.github.io/posts/20210719-ggctf2021-writeups/ (re/weather)
• https://pwnfirstsear.ch/2021/08/02/google2021-weather.html (re/weather)
• https://www.cis.upenn.edu/~hanbangw/blog/google-ctf-2021/#empty-ls (web/empty ls)
• https://github.com/luker983/google-ctf-2021/blob/main/web/empty-ls/README.md (web/empty ls)
• https://balsn.tw/ctf_writeup/20210717-googlectf2021/#empty-ls (web/empty ls)
• https://balsn.tw/ctf_writeup/20210717-googlectf2021/#gpushop (web/gpushop)
• https://balsn.tw/ctf_writeup/20210717-googlectf2021/#letschat (web/letschat)
  

If you have sent us a write-up, thank you for your submission!

If your write-up is listed above, we already sent you a separate e-mail.

-- Google CTF Team