# ASIS CTF 2022 Quals


* [Wormrep](#Wormrep-63)
* [Stacked QRs](#Stacked-QRs-83)
* [Comopti](#Compoti-114)

## Wormrep (63)


The challenge gave me a `.klr.enc1` file, after digging for a few minutes, I found out that was an encoded scan report from Kaspersky Virus Removal Tool.

So I downloaded KVRT, but before running it, I had to know how the tool reads the report file. Thanks to the [support page](https://support.kaspersky.com/15675) I had to rename the challenge file and put it in C:\KVRT2020\Data\Reports


Opening KVRT and go to report tab, sifted through the report, I found the flag.


<details>
<summary>Flag</summary>
ASIS{N07_@ll_v!ru535_@r3_AS_8@d_a5_cov!d}
</details>

## Stacked QRs (83)

Challenge gave me an image:

According to the description, `no important part of QRs is damaged`, that must mean only the position markers were overlapped.


After examining many QR codes that were mostly intact, I could safely assume the QRs had a dimension of 210x210 and the gaps between the QRs were 70 pixels.

I made a script to easily sift through the qr codes before fixing them

import cv2

img = cv2.copyMakeBorder(cv2.imread('stacked_qrs.png'), 0, 40, 0, 40, cv2.BORDER_CONSTANT, None, [255,255,255])

export = []

x, y = 0, 0

print(img.shape)

# cv2.imshow("original", img)
# cv2.waitKey(0)

for row in range(14):
    x = 0
    for column in range(14):
        crop = img[y:y+210,x:x+210]
        cv2.imshow("cropped", crop)
        key = cv2.waitKey(0)
        if(key == ord('s')):
            export.append(cv2.copyMakeBorder(crop,0,0,0,20,cv2.BORDER_CONSTANT, None, [255,0,128]))
        x += 70
    y+=70

concat_img = cv2.hconcat(export)
cv2.imwrite('.\\export.png',concat_img)
cv2.imshow('test',concat_img)
cv2.waitKey(0)

Got the QRs


Fixed them.


All I need to do is scan them

<details>
<summary>Flag</summary>
ASIS{7iM3_70_fix_7Hi5_0ld_diR7y_PRin73R!!}
</details>

## Compoti (114)

Challenge gave me a `.raw` file. After examining the file further, it was a reiser file system.

Using [rdrreiser](https://www.ufsexplorer.com/raise-data-recovery-reiser/), I could restore some files.


flag.txt was just a red herring. The other 2 files were Portable Gray Map Image, one was ASCII version and the other was binary version.

Looking inside the .pmg file, I could see comments and the file's width, height and max gray value were changed to 0.


I could replace the number 0 from the comment with spaces, and 9 from the image with spaces and get the message


OR I could edit the width, height and the max grey value then open the file in GIMP.


Decrypt with the given key gave me the flag.


<details>
<summary>Flag</summary>
ASIS{pgm_1M4gE_f0Rma7_ManUpL4T!On!}
</details>