UMDCTF Writeups
we settled for #43 from 484 teams
Misc⌗
more writeups from Mystik0ri0n here
John’s Return⌗
Description⌗
you can get the challenge file here
Solution⌗
summary :⌗
- WPA traffic decrypting
Here we have a pcapng file wirh 802.11 radiotap (wireless) traffic dump,seems it’s encrypted
…. but wait it’s a .pcapng file which aircrack-ng is unable to read it so we are forced to convert to a pcap i used this site pcapng.com for that then we can use aircrack-ng with rockyou.txt as our wordlist, seconds later it spits out the password
aircrack-ng received.s0i0.pcap -w /usr/share/wordlists/rockyou.txt
[00:00:00] 48/7120712 keys tested (2246.56 k/s)
Time left: 52 minutes, 50 seconds 0.00%
KEY FOUND! [ chocolate ]
Master Key : F8 FA E8 1B 93 20 46 CD F5 7C 0B 7C D0 70 0C 11
F5 70 AD 93 5B 9C 91 97 8D 44 18 70 76 56 5E B6
Transient Key : C7 DE 67 E5 E6 B2 C9 77 99 97 14 1C D2 88 60 60
10 05 FF CC 55 7A BF 51 63 CF 11 FilippoG98FilippoG98FilippoG9897 38 86 32 FF
AB 93 AA 76 0A E9 6B 85 72 70 26 ED 65 48 8C 44
22 A1 AC FA 0F 0B 6E 3D 1F 96 7B F7 C7 30 E5 54
EAPOL HMAC : B3 22 03 F5 85 25 3E 03 EE 64 24 6C C2 CB 77 76
using the password as chocolate
and the SSID as linksys
we can decrypt the traffic
open wireshark > edit > preferences > protocols > IEEE 802.11 > Enable Decryption > Key type : wpa-pwd > key password:SSID final as wpa-pwd chocolate:linksys
looking back at the decrpted traffic we get our flag in the decrypted CCMP data
Flag : UMDCTF-{wh3r3_j0hn}
Steganography⌗
Pickle Rick⌗
Challenge⌗
Solution⌗
We are given two rick rolls 😂 but both contain a hidden message, the first had the steg password for the second
┌─[@parrot]─[~/Desktop/CTFs/umdctf]
└──╼ $steghide extract -sf together-forever-encoded.wav
Enter passphrase:
wrote extracted data to "steganopayload318205.txt".
┌─[@parrot]─[~/Desktop/CTFs/umdctf]
└──╼ $cat steganopayload318205.txt
The password is "big_chungus"!
┌─[@parrot]─[~/Desktop/CTFs/umdctf]
└──╼ $steghide extract -sf rickroll.wav
Enter passphrase:
wrote extracted data to "steganopayload318287.txt".
┌─[@parrot]─[~/Desktop/CTFs/umdctf]
└──╼ $cat steganopayload318287.txt
UMDCTF-{n3v3r_g0nna_l3t_y0u_d0wn}
Flag : UMDCTF-{n3v3r_g0nna_l3t_y0u_d0wn}
Hidden Card⌗
Challenge⌗
Solution⌗
having tried majority of Steganographic techniques and failed,decided to try one last tool
opening the image in it and decoding using BattleSteg algorithm we get our Flag
┌─[@parrot]─[~/Desktop/CTFs/umdctf]
└──╼ $cat battle.txt
UMDCTF-{c4rd_1n_a_c4rd$t4ck}
Flag : UMDCTF-{c4rd_1n_a_c4rd$t4ck}