Lense Lense

## ctftime_scoreboard.py
#!/usr/bin/python3
import json

from CTFd import create_app
from CTFd.models import Users, Challenges


scoreboard = dict()
scoreboard["standings"] = list()

## fix_bold.diff
diff --git a/x.c b/x.c
index 5828a3b..ace044f 100644
--- a/x.c
+++ b/x.c
@@ -116,8 +116,6 @@ typedef struct {
 	int width;
 	int ascent;
 	int descent;
-	int badslant;
-	int badweight;

## README.md

      
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                CSAW quals 2015 forensics 400: Sharpturn
              
          
    First thing I did was figure out that it was a git repo, search Google for how to extract the code, and run
git archive master | tar x -C code. It asks for 2 prime factors of a number which doesn't have exactly 2 prime factors, from
which it can be assumed that something was wrong with the code.
Running git fsck (after more Google searching) showed 3 hashes not matching up, which means that the hash of the file contents
(plus header metadata) didn't match the filename. I then read https://git-scm.com/book/en/v2/Git-Internals-Git-Objects (side-note: the Pro Git book is a fantastic introduction to and reference for git).
3 Files are corrupted: sharp.cpp in each of the 3 commits (see git log).
Then I tool a leap of faith and assumed that a single byte was wrong (corrupted, hence the SATA controller comment) in each blob,
and wrote a script to brute force it. It worked for first one, and then doom had to remind me to propagate the changes: the first

  
## randomware.md

      
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                SECCON 2016 quals: randomware
              
          
    randomware

SECCON 2016 quals
description

300 points

My PC suddenly got broken. Could you help me to recover it please?

NOTE: The disk can be virus-infected. DO NOT RUN any programs extracted from the disk outside of sandbox.

disk.qcow2.zip

Challenge files is huge, please download it first. Password will release after 60min.

password: h9nn4c2955kik9qti9xphuxti

  
## brainfun.md

      
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                CSAW quals 2016 brainfun
              
          
    Challenge

Title: brainfun

Competition: CSAW quals 2016

Category: Forensics

Points: 150

Description: Scrambled Fun for Everyone! Author: fang0654 <brainfun.png>
Background


There's nothing hidden in the file other than the pixel data.
The image is 512x512, but can be scaled down 32x32 to match the blocks to


## challenge.md

      
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                CSAW 2014 quals: weissman (RE300.2) writeup
              
          
    Extract the key!
Written by RyanWithZombies
Update: The key is not "flag{ don't trust the Cheshire cat!! he works for the Queen of Hearts }". Sorry about that. It's an artifact from an easier version of this challenge. You need to extract key.jpg.
HINT:
CSAWLZ is a completely custom format! You won't find decompressing tools on the internet. We made it just for you. :)

  
## README.md

      
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                SECCON 2015--Find the prime numbers--Crypto200
              
          
    ###Good writeup is at https://github.com/p4-team/ctf/tree/master/2015-12-05-seccon/paillier_crypto_200#eng-version
I use the fact that h=co (mod n*n) to brute force n, which took around 45 minutes.

Then I factor n to get p and q, and make into phi.
Then I plug everything into the "simpler variant" on https://en.wikipedia.org/wiki/Paillier_cryptosystem

  
## sol
SOLARIZED HEX     16/8 TERMCOL  XTERM/HEX   L*A*B      RGB         HSB
--------- ------- ---- -------  ----------- ---------- ----------- -----------
base03    #002b36  8/4 brblack  234 #1c1c1c 15 -12 -12   0  43  54 193 100  21
base02    #073642  0/4 black    235 #262626 20 -12 -12   7  54  66 192  90  26
base01    #586e75 10/7 brgreen  240 #585858 45 -07 -07  88 110 117 194  25  46
base00    #657b83 11/7 bryellow 241 #626262 50 -07 -07 101 123 131 195  23  51
base0     #839496 12/6 brblue   244 #808080 60 -06 -03 131 148 150 186  13  59
base1     #93a1a1 14/4 brcyan   245 #8a8a8a 65 -05 -02 147 161 161 180   9  63
base2     #eee8d5  7/7 white    254 #e4e4e4 92 -00  10 238 232 213  44  11  93
base3     #fdf6e3 15/7 brwhite  230 #ffffd7 97  00  10 253 246 227  44  10  99

## CHALLENGE.md

      
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              September 22, 2015 19:27
            
              
                 CSAW quals 2015 crypto 200: punchout
              
          
    We found these System/360 punch cards and we need to extract the data. We already read the data off for you.
It looks encrypted. Can you help?
HINT: This is actually encrypted. With technology and techniques that were available in 1965
HINT: https://gist.github.com/withzombies/40554f02d6c7055fb0bc
punchout.tar.xz-24504ddc1e81092010497ee49fc52e1c

  
## solve_captured.py
#!/usr/bin/env python

# https://github.com/pablocelayes/rsa-wiener-attack
import RSAwienerHacker

def int2ascii(n):
	# Cut off 0x and L
	h = hex(n)[2:-1]
	# Convert each hex byte to ascii char
	return "".join([chr(int(h[i:i+2], 16)) for i in range(0, len(h), 2)])
	#!/usr/bin/python3
	import json

	from CTFd import create_app
	from CTFd.models import Users, Challenges


	scoreboard = dict()
	scoreboard["standings"] = list()
	diff --git a/x.c b/x.c
	index 5828a3b..ace044f 100644
	--- a/x.c
	+++ b/x.c
	@@ -116,8 +116,6 @@ typedef struct {
	int width;
	int ascent;
	int descent;
	- int badslant;
	- int badweight;
	SOLARIZED HEX 16/8 TERMCOL XTERM/HEX LAB RGB HSB
	--------- ------- ---- ------- ----------- ---------- ----------- -----------
	base03 #002b36 8/4 brblack 234 #1c1c1c 15 -12 -12 0 43 54 193 100 21
	base02 #073642 0/4 black 235 #262626 20 -12 -12 7 54 66 192 90 26
	base01 #586e75 10/7 brgreen 240 #585858 45 -07 -07 88 110 117 194 25 46
	base00 #657b83 11/7 bryellow 241 #626262 50 -07 -07 101 123 131 195 23 51
	base0 #839496 12/6 brblue 244 #808080 60 -06 -03 131 148 150 186 13 59
	base1 #93a1a1 14/4 brcyan 245 #8a8a8a 65 -05 -02 147 161 161 180 9 63
	base2 #eee8d5 7/7 white 254 #e4e4e4 92 -00 10 238 232 213 44 11 93
	base3 #fdf6e3 15/7 brwhite 230 #ffffd7 97 00 10 253 246 227 44 10 99
	#!/usr/bin/env python

	# https://github.com/pablocelayes/rsa-wiener-attack
	import RSAwienerHacker

	def int2ascii(n):
	# Cut off 0x and L
	h = hex(n)[2:-1]
	# Convert each hex byte to ascii char
	return "".join([chr(int(h[i:i+2], 16)) for i in range(0, len(h), 2)])