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##### Activity
zach mandeville
@zachmandeville_gitlab
beautiful
0xACAB
@fabacab
Yeah except I don't know what these values are.
zach mandeville
@zachmandeville_gitlab
If we put it in cyberchef, they all map to numbers:
26 5 26 9 25 22 26 25 26 9

and the repeated 26 (and that no number is higher) makes me sense it's an alphanumeric cipher.

If we say a is 1 and z is 26, then the decoded is zeziyvzyzi

if we say a is 26 and z is 1, then the decoded is avarbeabar which seems like not complete gibberish.

"a var be a bar"
0xACAB
@fabacab
Right, this is the CyberChef recipe, using the "From Binary" operation. (Just throwing this here so we can share and bookmark.)
I'm not convinced that's right and I don't think either rtcp{zeziyvzyzi} or rtcp{avarbeabar} work as flags.
zach mandeville
@zachmandeville_gitlab
Yah, it's not completely gibberish and it's not meaningful either. So far, the flags have all been some full english response to the challenge title.
and they've all been rctp{a_phrase_spaced_like_so}
0xACAB
@fabacab
I also don't know what the "From Binary" operation in CyberChef really does. If I run the first bit string we get into bc(1) I get this for various output bases:
echo "obase=16; ibase=2; 00110010" | bc
32
echo "obase=10; ibase=2; 00110010" | bc
50
echo "obase=08; ibase=2; 00110010" | bc
62
Oh wait I just realized what the From Binary operation does, lol. It turns it into ASCII. Because in ASCII, hex 32 is the ASCII 2, and so is decimal 50, and so is octal 62.
zach mandeville
@zachmandeville_gitlab
ah!
haha, but I still don't know what it means :/
0xACAB
@fabacab
Yeeeeeahâ€¦me neither.
I think your guess of it being an alphabet makes sense. 26 being the highest number is probably not a coincidence.

Also this:

for i in $(urldecode$(base64 --decode ~/Downloads/Beginner\ 10.txt | sed -e 's/^/%/' -e 's/ /%/g') | sed -e '-----/0/g' -e 's/.----/1/g' -e 's/ //g'); do printf "\x"$(echo "obase=16; ibase=2;$i" | bc) ; done
26 5 26 9 25 22 26 25 26 9

is the exact same output as from CyberChef, which proves that is in fact what it's doing. Unfortunately I don't know what these strings of numbers mean.

zach mandeville
@zachmandeville_gitlab

hmmm. the hint is 'hope you been paying attention', which ties to how many different decodings we've done so far, each being the answer to a previous q.

The other ciphers to try would be AZ126, Atbash, Bacon, and rot13/caesar

0xACAB
@fabacab
I tried a number of those in CyberChef already but couldn't make heads or tails of the output, though maybe I got the ordering wrong.
zach mandeville
@zachmandeville_gitlab
yah...and we've done the a1z26 and atbash already, and it doesn't look like a bacon cipher (that'd be a collection of 5 character strings like AAABB ABABA)
so really we'd just do rot13...but that doesn't give anything meaningful. I don't know, the distribution in that cipher seems weird. there's only 5 unique numbers/letters
0xACAB
@fabacab
It does seem a little short, but I'm fairly confident we aren't losing any data in the translation process.
0xACAB
@fabacab
So here is the entire CyberChef recipe for the challenge so far, and I think it's correct.
0xACAB
@fabacab
Welp, I'm gonna come back to this a bit later. That link should be sufficient for anyone else who wants to jump in and try to solve it with us.
aubrel
@aubrel

The people behind Covid Watch (https://www.covid-watch.org/about) are looking for help on Java development and/or help with containerizing their backend server:

https://github.com/Co-Epi/coepi-backend-aws

There's probably a lot more to do on that project, too, it seems cool!

Covid Watch aims to empower people to protect their communities from COVID-19 without sacrificing their personal privacy."

techlearningcollective
@techlearningcollective
We've opened our Hacker Trivia Night game weekend up for anyone who wants to play. Enjoy, especially if this is your first time. :)
yoni9091
@yoni9091
hey
where can i find the list of communities you support
?
techlearningcollective
@techlearningcollective
Our Web site's About page links out to all the groups we support in the various ways that we do.
0xACAB
@fabacab
There's another apparently noob-friendly CTF happening next week. Anyone from here into it? https://ctf.noobarmy.tech/
Olu v3.0.0
hey hey, are additional courses under development? Also, are there examples of what kind of time locally for you all the workshops would run at? In GMT so just checking before I get over excited :)
4 replies
techlearningcollective
@techlearningcollective
@/all We just released a new hybrid lab/project that combines topics from several workshops: run your own Tech Learning Collective Web site as a Tor Onion site (Dark Web site). Feel free to try it out and offer feedback here, via email, on GitHub, or during a workshop! Enjoy!
Leo
@immleo
bey guys, how does one get a pre-enrollment questionnaire?
2 replies
acoelho
@acoelho
Hey there, no instructor came to today's Guided Tour event, hope everything is okay!