Google CTF 2019 // #03-1 Work Computer
With the confidence of conviction and decision making skills that made you a contender for Xenon’s Universal takeover council, now disbanded, you forge ahead to the work computer. This machine announces itself to you, surprisingly with a detailed description of all its hardware and peripherals. Your first thought is “Why does the display stand need to announce its price? And exactly how much does 999 dollars convert to in Xenonivian Bucklets?” You always were one for the trivialities of things.
Also presented is an image of a fascinating round and bumpy creature, labeled “Cauliflower for cWo” – are “Cauliflowers” earthlings? Your 40 hearts skip a beat – these are not the strange unrelatable bipeds you imagined earthings to be.. this looks like your neighbors back home. Such curdley lobes. Will it be at the party?
SarahH, who appears to be a programmer with several clients, has left open a terminal. Oops. Sorry clients! Aliens will be poking around attempting to access your networks.. looking for Cauliflower. That is, *if* they can learn to navigate such things.
After trying out telnet and to find it not working, the next command I tried was netcat. Running a nc readme.ctfcompetition.com 1337 worked and I was connected to an Alien Shell. Running ls -lah and I see there are two filed in the shell.
- ———- 1 1338 1338 33 Feb 4 12:57 ORME.flag
- -r——– 1 1338 1338 28 Feb 4 12:57 README.flag
It is written that only the README.flag is readable
I tried multiple ways to access README.flag to no avail. Running tail, cat, vi, vim, nano all returned an error: No such file or directory.
I tried going one step up by running cd .. and realize there’s a /bin folder. I quickly traversed to that folder and did a folder listing.
After combing through the available applications and trying out multiple applications. I stumbled upon tar and running tar c ./ at the challenge directory actually listed out the contents of the files.
And with this, we found our third CTF flag.