TrollCat Forensics Writeups
Forbidden⌗
points 100
challenge description⌗
Agent Troll recieved some file but not able to read the data can you help us?
Author: White_Wolf Forbidden (link is dead but file is attached)
solution⌗
we are given a trollcats.car
$file trollcats.car
trollcats.car: data
on further investigation
$binwalk trollcats.car
DECIMAL HEXADECIMAL DESCRIPTION
--------------------------------------------------------------------------------
50 0x32 bzip2 compressed data, block size = 900k
extracting the file
$binwalk -e trollcats.car
DECIMAL HEXADECIMAL DESCRIPTION
--------------------------------------------------------------------------------
50 0x32 bzip2 compressed data, block size = 900k
┌─[@parrot]─[~/Desktop/CTFs/TrollCAT/Forensics]
└──╼ $cd _trollcats.car.extracted/
┌─[skoki@parrot]─[~/Desktop/CTFs/TrollCAT/Forensics/_trollcats.car.extracted]
└──╼ $ls
32
┌─[@parrot]─[~/Desktop/CTFs/TrollCAT/Forensics/_trollcats.car.extracted]
└──╼ $cat 32
Trollcat{M0zilla_Archive_maaaarls}
flag : Trollcat{M0zilla_Archive_maaaarls}
the_sus_agent⌗
points 251⌗
challenge description⌗
One of our agent is doing something suspicious on the network can you find out?
file Hint: If you got a string it’s useful somewhere but it’s not a flag
Author : white_wolf Mega link
solution⌗
we are given a sus_agent.pcapng
opening the pcap in wireshark
file > export objects > http > save all
gives us a bunch of files but two are important in this case
secret.jpg
and welcome.jpg
secret.jpg contains a base64 string
$cat secret.jpg
aWhvcGV5b3VkaWRub3R0cmllZHRvYnJ1dGVmb3JjZWl0
decoded to
$cat secret.jpg | base64 -d
ihopeyoudidnottriedtobruteforceit
which was the steghide password for welcome.jpg
[@parrot]─[~/Desktop/CTFs/TrollCAT/sus]
└──╼ $steghide extract -sf welcome.jpg
Enter passphrase:
the file "foryou" does already exist. overwrite ? (y/n) y
wrote extracted data to "foryou".
┌─[@parrot]─[~/Desktop/CTFs/TrollCAT/sus]
└──╼ $cat foryou
Trollcat{this_challenge_was_easy_right???}
flag : Trollcat{this_challenge_was_easy_right???}
s3cr3t⌗
points 495⌗
challenge description⌗
After getting trolled alot by Mr.Troll we finally got some files and now he’s hiding some secret with him your mission is to find that secret.
Challenge file link
Author: White_Wolf
NB://I did not solve this challenge on time
solution⌗
we are given a file trollcat.E01
of type
$file trollcat.E01
trollcat.E01: EWF/Expert Witness/EnCase image file format
using binwalk and other file carving tools will not be effective in this case so i decided to mount the image
sudo mkdir rawimage
sudo mkdir mountpoint
ewfmount file trollcat.E01 rawimage/
mount rawimage/ewf1 mountpoint/ -o ro,loop,show_sys_files,streams_interface=windows
the drive is now accesible and we can navigate through it
we get a topsecret.zip
under
favorites/drive
which contains an encrypted vhdx topsecret.vhdx
the following writeup was quite useful
https://stuxnet999.github.io/2021/02/06/trollcat-secret.html
Mr_evilpepo_1⌗
points 400⌗
We have caught Mr.EvilPepo and now it is time for you to investigate him we searched his house and we got not much proof we got some report from OSINT department and Our OSINT Investigator told us that he mentioned on his socials “Hack Me if you can, i use same password Everywhere” we have dumped his computer memory and for further investigation we need your help. he typed the flag command somewhere and now he forgot it. can you find it?
File: Challenge File
Flag Format: Trolcat{}
Author: White_wolf
solution⌗
in this we get a memory dump file evilpepo.vmem
from the hint : he typed the flag command somewhere and now he forgot it
we will use cmdscan
plugin to recover the flag
─[@parrot]─[~/Desktop/CTFs/TrollCAT/forensics]
└──╼ $volatility -f evilpepo.vmem --profile=Win7SP1x64 cmdscan
Volatility Foundation Volatility Framework 2.6
**************************************************
CommandProcess: conhost.exe Pid: 992
CommandHistory: 0x39eb60 Application: cmd.exe Flags: Allocated, Reset
CommandCount: 37 LastAdded: 36 LastDisplayed: 36
FirstCommand: 0 CommandCountMax: 50
ProcessHandle: 0x60
Cmd #0 @ 0x37e550: helo
Cmd #1 @ 0x37e570: troollll
Cmd #2 @ 0x37e590: caaat
Cmd #3 @ 0x37e5b0: yooooo
Cmd #4 @ 0x39de90: T
Cmd #5 @ 0x39dcd0: r
Cmd #6 @ 0x3a2f00: o
Cmd #7 @ 0x3a2f20: l
Cmd #8 @ 0x3a2f40: c
Cmd #9 @ 0x3a2f60: a
Cmd #10 @ 0x3a2fb0: t
Cmd #11 @ 0x3a2fc0: {
Cmd #12 @ 0x3a2fd0: c
Cmd #13 @ 0x3a2fe0: o
Cmd #14 @ 0x3a2ff0: m
Cmd #15 @ 0x3a3000: a
Cmd #16 @ 0x3a3010: n
Cmd #17 @ 0x3a3020: d
Cmd #18 @ 0x3a3030: s
Cmd #19 @ 0x3a3040: _
Cmd #20 @ 0x3a3050: 4
Cmd #21 @ 0x3a3060: r
Cmd #22 @ 0x3a3070: 3
Cmd #23 @ 0x3a3080: _
Cmd #24 @ 0x3a3090: i
Cmd #25 @ 0x3a30a0: m
Cmd #26 @ 0x3a30b0: p
Cmd #27 @ 0x3a30c0: o
Cmd #28 @ 0x3a30d0: r
Cmd #29 @ 0x3a30e0: t
Cmd #30 @ 0x3a30f0: a
Cmd #31 @ 0x3a3100: n
Cmd #32 @ 0x3a3110: t
Cmd #33 @ 0x3a3120: }
Cmd #34 @ 0x3a33b0: hope you got it
Cmd #35 @ 0x377860: "are you trying to run strings?"
Cmd #36 @ 0x3a33e0: lolololololol
flag : Trolcat{commands_4r3_important}
Mr_evilpepo_2⌗
points 496
challenge description⌗
Now After some good beating, Mr.EvilPepo saying he hides something on the internet. find it
Note: Use the file provided in Mr.EvilPepo Part-1
AUTHOR: WHITE_WOLF
solution⌗
same file as above for this challenge
from the hint ...he hides something on the internet. find it
we need to check through some browswer history
┌─[skoki@parrot]─[~/Desktop/CTFs/TrollCAT/forensics]
└──╼ $volatility -f evilpepo.vmem --profile=Win7SP1x64 pstree
Volatility Foundation Volatility Framework 2.6
Name Pid PPid Thds Hnds Time
-------------------------------------------------- ------ ------ ------ ------ ----
0xfffffa8000ca0ae0:System 4 0 78 506 2021-01-12 13:13:38 UTC+0000
. 0xfffffa8001bf6470:smss.exe 256 4 2 29 2021-01-12 13:13:38 UTC+0000
0xfffffa80028a7630:csrss.exe 388 368 11 338 2021-01-12 13:13:53 UTC+0000
. 0xfffffa8000f0d060:conhost.exe 992 388 2 51 2021-01-12 13:20:09 UTC+0000
0xfffffa80028f9480:winlogon.exe 420 368 3 109 2021-01-12 13:13:53 UTC+0000
0xfffffa800344fb30:explorer.exe 1568 1548 32 895 2021-01-12 13:14:47 UTC+0000
. 0xfffffa80020de060:notepad.exe 3120 1568 1 61 2021-01-12 13:22:27 UTC+0000
. 0xfffffa8003428a30:cmd.exe 1492 1568 1 19 2021-01-12 13:20:08 UTC+0000
. 0xfffffa8003673b30:chrome.exe 1932 1568 34 856 2021-01-12 13:15:05 UTC+0000
.. 0xfffffa80036d6b30:chrome.exe 912 1932 8 84 2021-01-12 13:15:12 UTC+0000
.. 0xfffffa8000ee9b30:chrome.exe 1292 1932 13 204 2021-01-12 13:16:11 UTC+0000
.. 0xfffffa8000e9ab30:chrome.exe 2324 1932 13 255 2021-01-12 13:16:05 UTC+0000
.. 0xfffffa8000da1b30:chrome.exe 2352 1932 20 248 2021-01-12 13:15:37 UTC+0000
.. 0xfffffa8000e5cb30:chrome.exe 2896 1932 8 181 2021-01-12 13:15:54 UTC+0000
.. 0xfffffa8000d97b30:chrome.exe 2556 1932 7 131 2021-01-12 13:15:38 UTC+0000
. 0xfffffa8000fc0060:KeePass.exe 3908 1568 12 324 2021-01-12 13:18:05 UTC+0000
0xfffffa80028ba060:csrss.exe 328 320 8 405 2021-01-12 13:13:52 UTC+0000
0xfffffa80027ddb30:wininit.exe 376 320 3 74 2021-01-12 13:13:53 UTC+0000
. 0xfffffa8002da0b30:services.exe 472 376 11 192 2021-01-12 13:13:59 UTC+0000
.. 0xfffffa8003180890:svchost.exe 268 472 19 484 2021-01-12 13:14:12 UTC+0000
.. 0xfffffa8002fab440:svchost.exe 668 472 8 261 2021-01-12 13:14:06 UTC+0000
.. 0xfffffa800142db30:sppsvc.exe 1456 472 4 142 2021-01-12 13:16:56 UTC+0000
.. 0xfffffa8003236610:svchost.exe 4016 472 16 344 2021-01-12 13:18:10 UTC+0000
.. 0xfffffa80030d5b30:svchost.exe 808 472 16 311 2021-01-12 13:14:06 UTC+0000
... 0xfffffa8003441b30:dwm.exe 1556 808 3 80 2021-01-12 13:14:47 UTC+0000
.. 0xfffffa8003146b30:svchost.exe 968 472 29 448 2021-01-12 13:14:11 UTC+0000
.. 0xfffffa8003229570:svchost.exe 948 472 21 332 2021-01-12 13:14:18 UTC+0000
.. 0xfffffa80032145c0:spoolsv.exe 832 472 13 265 2021-01-12 13:14:17 UTC+0000
.. 0xfffffa80030d3b30:svchost.exe 836 472 41 1162 2021-01-12 13:14:06 UTC+0000
.. 0xfffffa8003091370:svchost.exe 716 472 26 521 2021-01-12 13:14:06 UTC+0000
... 0xfffffa8003116060:audiodg.exe 916 716 6 131 2021-01-12 13:14:09 UTC+0000
.. 0xfffffa800347b890:taskhost.exe 1748 472 8 142 2021-01-12 13:14:48 UTC+0000
.. 0xfffffa8002feb970:svchost.exe 600 472 10 348 2021-01-12 13:14:05 UTC+0000
... 0xfffffa8000ff1060:dllhost.exe 2920 600 9 198 2021-01-12 13:19:42 UTC+0000
... 0xfffffa8000ea3060:dllhost.exe 1852 600 6 89 2021-01-12 13:22:36 UTC+0000
... 0xfffffa8000dc3b30:WmiPrvSE.exe 3400 600 7 114 2021-01-12 13:19:14 UTC+0000
.. 0xfffffa80023e2060:svchost.exe 784 472 25 264 2021-01-12 13:15:13 UTC+0000
.. 0xfffffa800183f650:wmpnetwk.exe 1640 472 11 218 2021-01-12 13:15:01 UTC+0000
.. 0xfffffa80032173b0:SearchIndexer. 1832 472 12 702 2021-01-12 13:15:00 UTC+0000
... 0xfffffa8003696b30:SearchProtocol 1960 1832 8 387 2021-01-12 13:15:05 UTC+0000
... 0xfffffa8000d9bb30:SearchFilterHo 1504 1832 6 150 2021-01-12 13:20:40 UTC+0000
. 0xfffffa8002811b30:lsass.exe 480 376 7 553 2021-01-12 13:13:59 UTC+0000
. 0xfffffa80020b7b30:lsm.exe 488 376 10 149 2021-01-12 13:13:59 UTC+0000
we can see two browsers in use
explorer
and chrome
volatility lacks an inbuilt plugin for firefox and chrome so we will use a third party for the same
guide and plugins
https://blog.superponible.com/2014/08/31/volatility-plugin-chrome-history/
https://github.com/superponible/volatility-plugins
volatility --plugins=volatility-pluginss/ -f evilpepo.vmem --profile=Win7SP1x64 chromehistory
Volatility Foundation Volatility Framework 2.6
Index URL
https://defuse.ca/b/sOOqp4UunTdD0oUjidJFlz Defuse Security's Encrypted Pastebin 2 1 2021-01-12 08:23:00.706346 N/A
snipped for readability
following the links gives us an encrypted pastebin which needs a password to reveal the flag …..
looking back at the pstree
results we can see lsass.exe
Local Security Authority Subsystem Service (LSASS) is a process in Microsoft Windows operating systems that is responsible for enforcing the security policy on the system. It verifies users logging on to a Windows computer or server, handles password changes, and creates access tokens
for this i will use the hashdump
plugin to recover NTLM hashes for all users
┌─[✗]─[@parrot]─[~/Desktop/CTFs/TrollCAT/forensics]
└──╼ $volatility -f evilpepo.vmem --profile=Win7SP1x64 hashdump
Volatility Foundation Volatility Framework 2.6
Administrator:500:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
Guest:501:aad3b435b51404eeaad3b435b51404ee:31d6cfe0d16ae931b73c59d7e0c089c0:::
WhiteWolf:1000:aad3b435b51404eeaad3b435b51404ee:2e6a7cf5aabb33a044684dd9c97e88a7:::
user WhiteWolf since he was the author
echo "2e6a7cf5aabb33a044684dd9c97e88a7" > hash.txt
john --format=nt hash.txt
hashcat -m 1000 -a 3 hash.txt
cracking the NTLM hash for user WhiteWolf
reveals the password as abracadabra
using the password we can now decrypt our encrypted pastebin to reveal the flag
flag : Trollcat{secret_hidden_0nn_th3_1ntern3t}
alternatively you can use mimikatz plugin
Mr_evilpepo_3⌗
points 498⌗
challenge description⌗
The Top Secret file of Mr.EvilPepo is still not discovered this is your last mission of finding the top secret file related to Mr.EvilPepo Good Luck
Note: Use the file provided in Mr.EvilPepo Part-1
AUTHOR: WHITE_WOLF
i did not solve this challenge on time,
i do recommend reading the following writeup
https://stuxnet999.github.io/2021/02/06/trollcat-mrevilpepo.html
….. Thank you for your time,hope you learnt something new :)