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Corne's Lost Password

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68
hyperastro
63 posts
Joined May 2023
Topic Starter
hyperastro
Corne's Lost Password




Something strange has happened in OT…

Corne2Plum3 was trying to figure out how to lock threads when he accidentally logged himself out.

No big deal, right? Just reset the password.But sadly the recovery email didn’t work. All that Corne is left with is a scrambled piece of text.

033d3804127f100d04445020203e1d1c7f09040f

This ciphertext looks like nonsense, but it actually contains Corne's password which he can use to log back into his account.

Problem is, The cipher isn’t simple. But by some divine intervention hints and parts of the key were sent to various OT'ers

Some of you have received fragments of the key. Others have hints about the password inside. But no single person can solve it alone. You’ll need to work together, combine your clues, and see if OT can prove itself as a team.

The question is:
Can OT save Corne's account… or will his password be lost forever?

Premise of this thread:

- OTers must work toghter to find Corne's password.
- The password can be found with any 5 hints but the more you have the more obvious it becomes.
- If you don't wish to participate in this thread but you received a DM, reply to this thread with the hint to help.
- if you usually don't check your DM's check them! see if you have a hint
- This is a test to see how well OT can work as a team.
Last edited by hyperastro , edited 1 time in total.
Ashton
2,039 posts
Joined February 2016
Ashton
Hint: the 2nd word of the plain text is the most common English word
Behrauder
95 posts
Joined June 2021
Behrauder
XOR:

-Izuki-
9,487 posts
Joined December 2023
-Izuki-
Hint: The 3rd word of plaintext is a vegetable.
tapperruiii
75 posts
Joined July 2024
tapperruiii
Hint: 6th to 10th character spell a real word
Isshiki Kaname
936 posts
Joined May 2014
Isshiki Kaname
Hint: my bro made a watermelon fountain
McEndu
1,398 posts
Joined March 2019
McEndu
Hint: Not Ceasar, not Atbash.

The piece of scrambled text is hexadecimal with 40 characters. (Take: SHA-1 hash seems plausible.)
Last edited by McEndu , edited 1 time in total.
z0z
521 posts
Joined February 2018
z0z
Hint: 6th character is an underscore
Ymir
1,935 posts
Joined June 2020
Ymir
Hint: Someone's hint is a lie.
McEndu
1,398 posts
Joined March 2019
McEndu

Ashton wrote:

Hint: the 2nd word of the plain text is the most common English word
Take: "the"

Some places (e.g. Linux?) allows spaces (U+0020, ASCII 0x20) in passwords, others do not
Last edited by McEndu , edited 1 time in total.
Gengar9nn
338 posts
Joined October 2022
Gengar9nn
Hint: 10 characters long
Last edited by Gengar9nn , edited 1 time in total.
McEndu
1,398 posts
Joined March 2019
McEndu

Gengar9nn wrote:

Hint: 10 characters long
Take: without other hints and assuming only ASCII characters (excluding C0 control codes, space and U+007F DELETE) are used, search space is somewhere between 2^65 to 2^66

Ashton wrote:

Hint: the 2nd word of the plain text is the most common English word
There are the following possibilities:

.the......
..the.....
...the....
....the...
.....the..
......the.
.......the

reducing the search space to 7x(94^7), or slightly lower than 2^46, a few magnitutes easier than cracking DES. If the string is indeed a SHA-1 hash, it shouldn't take long to crack the password by force unless there is a yet unknown salt string.

Ymir wrote:

Hint: Someone's hint is a lie.

z0z wrote:

Hint: 6th character is an underscore

tapperruiii wrote:

Hint: 6th to 10th character spell a real word
Take: the lie is either z0z's hint or tapperruiii's hint.
-Izuki-
9,487 posts
Joined December 2023
-Izuki-

McEndu wrote:

Take: the lie is either z0z's hint or tapperruiii's hint.
Or ymir is just a lier ¯\_(ツ)_/¯
McEndu
1,398 posts
Joined March 2019
McEndu

-Izuki- wrote:

Hint: The 3rd word of plaintext is a vegetable.
Take: The password is either in the form ??the_???? (z0z) or ??the????? (tapperuiii).

At this point a Python script could be used to crack this in 24 hours with a dictionary attack, imo.
Last edited by McEndu , edited 1 time in total.
hyperastro
63 posts
Joined May 2023
Topic Starter
hyperastro
(Extra Hint): Ppy didn't use best practices when creating the website and he did not adhere by modern cyber security standards. He might not have been aware about concepts such as password hashing and opted to use a diffrent route.
- Marco -
Technical Support Team
8,498 posts
Joined December 2011
- Marco -
Hint: One of the most common thread types in OT
-Izuki-
9,487 posts
Joined December 2023
-Izuki-

hyperastro wrote:

(Extra Hint): Ppy didn't use best practices when creating the website and he did not adhere by modern cyber security standards. He might not have been aware about concepts such as password hashing and opted to use a diffrent route.
probably API key, but idk how it actually can help
McEndu
1,398 posts
Joined March 2019
McEndu

- Marco - wrote:

Hint: One of the most common thread types in OT
Take: ITT?
Corne2Plum3
Global Moderator
1,870 posts
Joined November 2019
Corne2Plum3
Hint: the cipher uses a logical operation found in computer science
- Marco -
Technical Support Team
8,498 posts
Joined December 2011
- Marco -

McEndu wrote:

- Marco - wrote:

Hint: One of the most common thread types in OT
Take: ITT?
or AMA 🤔
MangaGrumpy
374 posts
Joined May 2022
MangaGrumpy

- Marco - wrote:

McEndu wrote:

- Marco - wrote:

Hint: One of the most common thread types in OT
Take: ITT?
or AMA 🤔
No it's like meta or something when was the last time an itt thread was posted
burgernfat
22 posts
Joined March 2021
burgernfat
By divine intervention you have been gifted with a hint for this thread: community/forums/topics/2125918?n=1 Hint: Together the plaintext has 4 words
4:43
Karmine
1,031 posts
Joined November 2015
Karmine
Hint: happy->sad peace->war alive->___
Gengar9nn
338 posts
Joined October 2022
Gengar9nn

Karmine wrote:

Hint: happy->sad peace->war alive->___
dead
Gengar9nn
338 posts
Joined October 2022
Gengar9nn

Corne2Plum3 wrote:

Hint: the cipher uses a logical operation found in computer science
Isn't your password lost?
ynzoqn
8 posts
Joined May 2024
ynzoqn 
echo "033d3804127f100d04445020203e1d1c7f09040f" | xxd -r -p
Will this help? I'm just guessing.
McEndu
1,398 posts
Joined March 2019
McEndu
Edit: fairly unlikely to be a SHA-1 hash imo, all bytes are in the 0x00-0x7f range :shrug:
ynzoqn
8 posts
Joined May 2024
ynzoqn
3, 61, 56, 4, 18, 127, 16, 13, 4, 68
80, 32, 32, 62, 29, 28, 127, 9, 4, 15

83 93 88 64 47 99 111 105 119 83
S]X@/coiwS
Could this be the answer?
Gengar9nn
338 posts
Joined October 2022
Gengar9nn

ynzoqn wrote:

3, 61, 56, 4, 18, 127, 16, 13, 4, 68
80, 32, 32, 62, 29, 28, 127, 9, 4, 15

83 93 88 64 47 99 111 105 119 83
S]X@/coiwS
Could this be the answer?
Unless there's a second cipher applied here, no
Corne2Plum3
Global Moderator
1,870 posts
Joined November 2019
Corne2Plum3

ynzoqn wrote:

3, 61, 56, 4, 18, 127, 16, 13, 4, 68
80, 32, 32, 62, 29, 28, 127, 9, 4, 15
Tried several 8-bit bitwise operations between these 2 lists and convert to ASCII:
  1. AND: 0, 32, 32, 4, 16, 28, 16, 9, 4, 4 
    <Literally nothing is displayed>
  2. OR: 83, 61, 56, 62, 31, 127, 127, 13, 4, 79 
    O=8>
  3. XNOR: 172, 194, 199, 193, 224, 128, 128, 242, 251, 176 
    ¬ÂÇÁàòû°
  4. NAND: 255, 223, 223, 251, 239, 227, 239, 246, 251, 251 
    ÿßßûïãïöûû
Tried the same but with 7 bits (getting rid of the most significant bit by using a 0x7F mask):
  1. AND: 0, 32, 32, 4, 16, 28, 16, 9, 4, 4 
    <Literally nothing is displayed>
  2. OR: 83, 61, 56, 62, 31, 127, 127, 13, 4, 79 
    O=8>
  3. XNOR: 44, 66, 71, 65, 96, 0, 0, 114, 123, 48 
    ,BGA`r{0
  4. NAND: 255, 223, 223, 251, 239, 227, 239, 246, 251, 251 
    __{ocov{{
I don't think I'm getting anywhere with this...
hyperastro
63 posts
Joined May 2023
Topic Starter
hyperastro
This is so interesting to watch!!!

Just a little nudge to make sure you guys don't go the completely wrong route. There is only 1 cipher applied. Re-read the hints that were sent in chat (yall are so close but so far)
Gengar9nn
338 posts
Joined October 2022
Gengar9nn

hyperastro wrote:

This is so interesting to watch!!!

Just a little nudge to make sure you guys don't go the completely wrong route. There is only 1 cipher applied. Re-read the hints that were sent in chat (yall are so close but so far)
Yeah
abraker
Global Moderator
8,356 posts
Joined July 2014
abraker
I was going to berate hyperastro for making this gpt crackable but I am pleasantly surprised

Ashton
2,039 posts
Joined February 2016
Ashton

abraker wrote:

I was going to berate hyperastro for making this gpt crackable but I am pleasantly surprised

Yeah thats one of the first thing I did until I realized it was much more complicated lol
ynzoqn
8 posts
Joined May 2024
ynzoqn
Now I'm thinking it might be the sha1sum, which is 40 characters long. There are four words, the second word is "the", the third word is some kind of vegetable, and characters 6 through 10 form a word. Storing the password in this way in a database doesn't seem secure. It might be something like this.

printf "celebration the pumpkin spice" | sha1sum
87bf107cf65f071bc4b6f6a4d35a09be57cff278
Karmine
1,031 posts
Joined November 2015
Karmine
Is it even possible? I've tried but couldn't get anything conclusive there's contradictory info it seems.

According to hints there are 4 words and 10 characters total, that's only 1 to 3 letter words, one of them being "the".
There's supposed to be a vegetable name but is there even one that would fit? And then there's either a 5 letter word on 6-10 or an underscore on 6.
hyperastro
63 posts
Joined May 2023
Topic Starter
hyperastro

Karmine wrote:

Is it even possible? I've tried but couldn't get anything conclusive there's contradictory info it seems.

According to hints there are 4 words and 10 characters total, that's only 1 to 3 letter words, one of them being "the".
There's supposed to be a vegetable name but is there even one that would fit? And then there's either a 5 letter word on 6-10 or an underscore on 6.
Some clues are related to the plaintext answer others have to do with the key. (Look at the cipher text there might be a pattern you can find)
Last edited by hyperastro , edited 1 time in total.
ynzoqn
8 posts
Joined May 2024
ynzoqn
It needs to be encrypted with a key, so it's not SHA-1. I should have realized this from the Extra Hint and McEndu's post, but I was too eager to believe it was SHA-1.
McEndu
1,398 posts
Joined March 2019
McEndu

hyperastro wrote:

Karmine wrote:

Is it even possible? I've tried but couldn't get anything conclusive there's contradictory info it seems.

According to hints there are 4 words and 10 characters total, that's only 1 to 3 letter words, one of them being "the".
There's supposed to be a vegetable name but is there even one that would fit? And then there's either a 5 letter word on 6-10 or an underscore on 6.
Some clues are related to the plaintext answer others have to do with the key. (Look at the cipher text there might be a pattern you can find)
guess on encryption scheme: ciphertext[20] = plaintext[20] XOR concat(key[10], key[10])
tapperruiii
75 posts
Joined July 2024
tapperruiii
how are yall this nerdy
McEndu
1,398 posts
Joined March 2019
McEndu
Made a script to help determine where "the" should be in the key or plain text

Results:

77 55 5d wU]
49 50 61 IPa
4c 6c 77 Llw
70 7a 1a pz.
66 17 75 f.u
0b 78 68 .xh
64 65 61 dea
79 6c 21 yl!
70 2c 35 p,5
30 38 45 08E
24 48 45 $HE
54 48 5b TH[
54 56 78 TVx
4a 75 79 Juy
69 74 1a it.
68 17 6c h.l
0b 61 61 .aa
7d 6c 6a }lj

source
#include <stdio.h>
#include <string.h>

static const char ctext[] = {
    0x03, 0x3d, 0x38, 0x04, 0x12, 0x7f, 0x10, 0x0d, 0x04, 0x44,
    0x50, 0x20, 0x20, 0x3e, 0x1d, 0x1c, 0x7f, 0x09, 0x04, 0x0f,
};

int main()
{
    char window[4];
    window[3] = 0;

    for (int i = 0; i <= 17; ++i) {
        memcpy(window, &ctext[i], 3);
        window[0] ^= 't';
        window[1] ^= 'h';
        window[2] ^= 'e';
        printf("%02x %02x %02x %3s\n", window[0], window[1], window[2], window);
    }

    return 0;
}

tapperruiii wrote:

how are yall this nerdy
this is nerd thread sorry
Last edited by McEndu , edited 1 time in total.
hyperastro
63 posts
Joined May 2023
Topic Starter
hyperastro

McEndu wrote:

hyperastro wrote:

Karmine wrote:

Is it even possible? I've tried but couldn't get anything conclusive there's contradictory info it seems.

According to hints there are 4 words and 10 characters total, that's only 1 to 3 letter words, one of them being "the".
There's supposed to be a vegetable name but is there even one that would fit? And then there's either a 5 letter word on 6-10 or an underscore on 6.
Some clues are related to the plaintext answer others have to do with the key. (Look at the cipher text there might be a pattern you can find)
guess on encryption scheme: ciphertext[20] = plaintext[20] XOR concat(key[10], key[10])
👀
McEndu
1,398 posts
Joined March 2019
McEndu
If XOR is correct, the reuse of one-time-pad gives a fairly meaty attack vector.

XOR of the halves: 53 1d 18 3a 0f 63 6f 04 00 4b

Guess of character classes, assuming no control characters (0x00-0x1f and 0x7f):

  1. number/lowercase
  2. same class
  3. same class
  4. uppercase/lowercase
  5. same class
  6. number/uppercase
  7. number/uppercase
  8. same class
  9. same class
  10. number/lowercase
Legend:
  1. C0: control characters (0x00 - 0x1f)
  2. number: numbers and a majority of punctuations including space (0x20 - 0x3f)
  3. uppercase: uppercase letters and some punctuations (0x40 - 0x5f)
  4. lowercase: lowercase letters and some punctuations (0x60 - 0x7f)
  5. same class: any of number/number, uppercase/uppercase or lowercase/lowercase
Last edited by McEndu , edited 3 times in total.
ynzoqn
8 posts
Joined May 2024
ynzoqn
https://crypto.stackexchange.com/a/10163
https://toolbox.lotusfa.com/crib_drag/
https://www.tausquared.net/pages/ctf/twotimepad
I don't know if this is useful. There should be the in the plain text. If this approach is used, the total length of the four words of plaintext plus any spaces should be 20 characters.
Last edited by ynzoqn , edited 3 times in total.
ynzoqn
8 posts
Joined May 2024
ynzoqn
I think it may not be related to Two-Time Pad. When I use this webpage, I see that the visible characters include spaces, numbers, etc., which do not look like regular words.

Last edited by ynzoqn , edited 1 time in total.
ynzoqn
8 posts
Joined May 2024
ynzoqn
https://blog.ppy.sh/post/128722315598/20150909

It seems that bcrypt has been used since at least 2015. We may need to find posts on sites such as reddit before 2015 to find the cipher?

I looked through pages 25 to 45 of blog.ppy.sh, which dates back to September 9, 2015, and found nothing about storing passwords in databases. However, I did find some other interesting content, which I found in the following links:

osu!stamp
https://blog.ppy.sh/post/121343692948/20150612-answers
https://blog.ppy.sh/post/121948609343/20150619-answers-2
https://blog.ppy.sh/post/122576677808/20150627-answers-3
https://blog.ppy.sh/post/123257459803/20150705-answers-4
https://blog.ppy.sh/post/123968773293/20150713
https://blog.ppy.sh/post/124649324483/20150721
https://blog.ppy.sh/post/126660263353/20150814
https://blog.ppy.sh/post/128102417423/20150901
Last edited by ynzoqn , edited 1 time in total.
Karmine
1,031 posts
Joined November 2015
Karmine
This is getting too deep. :cry:
McEndu
1,398 posts
Joined March 2019
McEndu

ynzoqn wrote:

https://blog.ppy.sh/post/128722315598/20150909

It seems that bcrypt has been used since at least 2015. We may need to find posts on sites such as reddit before 2015 to find the cipher?

I looked through pages 25 to 45 of blog.ppy.sh, which dates back to September 9, 2015, and found nothing about storing passwords in databases. However, I did find some other interesting content, which I found in the following links:

osu!stamp
https://blog.ppy.sh/post/121343692948/20150612-answers
https://blog.ppy.sh/post/121948609343/20150619-answers-2
https://blog.ppy.sh/post/122576677808/20150627-answers-3
https://blog.ppy.sh/post/123257459803/20150705-answers-4
https://blog.ppy.sh/post/123968773293/20150713
https://blog.ppy.sh/post/124649324483/20150721
https://blog.ppy.sh/post/126660263353/20150814
https://blog.ppy.sh/post/128102417423/20150901
I don't think this is a real entry from the production database.
hyperastro
63 posts
Joined May 2023
Topic Starter
hyperastro

Karmine wrote:

This is getting too deep. :cry:
Mariana trench levels of deep...
McEndu
1,398 posts
Joined March 2019
McEndu
How many words for vegetables are in the Oxford dictionary, sorted by number of alphabets? just to know
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