9.3 KiB
Introduction
The Launch Instances module (aws_launch_instances
) can be used to launch a
Cloud host running metasploit-aggregator (a proxy for Meterpreter sessions).
TLDR
Shell #1:
> use auxiliary/admin/aws/aws_launch_instances
> set AccessKeyId ...
> set SecretAccessKey ...
> set SSH_PUB_KEY ssh-rsa ABCDEDG123...
> set SEC_GROUP_CIDR <MY IP ADDRESS>/32
> run
[*] Created security group: sg-abcdefg
[*] Launching instance(s) in us-west-2, AMI: ami-1e299d7e, key pair name: admin, security group: sg-abcdefg, subnet ID: subnet-hijklmn
[*] Launched instance i-12345678 in us-west-2 account 012345678900
[*] instance i-12345678 status: initializing
...
[*] instance i-12345678 status: ok
[*] Instance i-12345678 has IP address 35.12.4.1
[*] Auxiliary module execution completed
Shell #2:
ssh ec2-user@35.12.4.1 -L 2447:127.0.0.1:2447
Shell #1 again:
> load aggregator
> aggregator_connect 127.0.0.1:2447
For more information on metasploit-aggregator, see https://github.com/rapid7/metasploit-aggregator
Background
AWS API Access Keys
API access keys can be used to make calls against the AWS API, to say retrieve deployment packages from S3.
VPC
The VPC or Virtual Private Cloud, an isolated local area network. Network access can be made available by assigning an Internet routable IP address to a host or routing traffic to it through an ELB (Elastic Load Balancer). In either case security-groups are used to open access to network ranges and specific TPC/UDP ports. Security-groups provide much of the functionality of traditional firewalls and can be configured by specifying a protocol, a CIDR and a port.
How it Works
Although hosts can be launched using the Web console or the CLI, launching a host in the Cloud requires a fair amount of configuration; this module does its best to abstract configuration requirements away from the user by auto detecting the VPC, subnets, creating security groups, etc. It performs several tasks to launch a host with a public IP address, these are as follow: 1) select a VPC, 2) select a subnet, 3) create/select a security group, 4) create/select a key-pair, and 5) launch a host.
The module will attempt to launch the host in the first VPC it finds in the
given region (Region
option). Most of the time there is only one VPC per
account per region, however one might find multiple VPCs within the same region.
In this case, one may use the VPC_ID
advanced option to specify the VPC to
use. Selecting a subnet is a bit more complicated. To have traffic routed
between us and the Cloud host, a public subnet (a subnet that is routable to an
Internet gateway) must be selected and the Cloud host must be associated with
an Internet routable IP address. The module dynamically finds which subnet to
launch the host in. It will use the first subnet it finds having the
Auto-assign Public IP
option set, if no such subnet exists, then it will
select the first subnet having an Internet gateway. To circumvent this process,
the SUBNET_ID
advanced option can be set.
When launching a Cloud host at least one security group is required. There are
several advanced options for creating/selecting a security group. The
SEC_GROUP_ID
option works much in the same way the VPC_ID
option does.
That is, the module will create a security group unless the SEC_GROUP_ID
options is set. If the SEC_GROUP_ID
option is not set, the module will attempt
to create a security group using the values specified in the SEC_GROUP_CIDR
,
SEC_GROUP_NAME
, and SEC_GROUP_PORT
options as configuration.
The KEY_NAME
and SSH_PUB_KEY
options are used in conjunction to select or
create a key-pair (a named SSH public key). Key-pairs are used to authenticate
to the host once it is running. The KEY_NAME
defaults to admin while
SSH_PUB_KEY
is optional. If the SSH_PUB_KEY
is left unset, then the module
will not attempt to create a key-pair and will simply attempt to launch the
instance using an existing key-pair denoted by KEY_NAME
. To set the
SSH_PUB_KEY
option, a public SSH key must be provided as can be generated by
ssh-keygen -y -f <private key filename>
. Once a key-pair is created/selected,
the module launches the host via the AWS API specifying that it should
associate a public IP address.
As part of launching the host it passes user-data (shell script) that installs metasploit-aggregator and runs it in a screen session.
Options
The Launch Instances module is an auxiliary module that can be loaded using the
use command. To run the module, only the AccessKeyId
, SecretAccessKey
, and
KEY_NAME
options are required.
Basic Options:
AMI_ID
: The Amazon Machine Image (AMI) ID (region dependent)RHOST
: the AWS EC2 Endpoint (ec2.us-west-2.amazonaws.com), may change this to something closer to youRegion
: The default region (us-west-2), must match endpointAccessKeyId
: AWS API access keySecretAccessKey
: AWS API secret access keyToken
: AWS API session token, optionalKEY_NAME
: The SSH key to be used for ec2-userSSH_PUB_KEY
: The public SSH key to be used for ec2-user, e.g., "ssh-rsa ABCDE..."USERDATA_FILE
: The script that will be executed on start
Advanced Options:
INSTANCE_TYPE
: The instance typeMaxCount
: Maximum number of instances to launchMinCount
: Minimum number of instances to launchROLE_NAME
: The instance profile/role nameRPORT:
AWS EC2 Endpoint TCP PortSEC_GROUP_ID
: the EC2 security group to useSEC_GROUP_CIDR
: the EC2 security group network access CIDR, defaults to 0.0.0.0/0SEC_GROUP_NAME
: the EC2 security group nameSEC_GROUP_PORT
: the EC2 security group network access port, defaults to tcp:22SUBNET_ID
: The public subnet to useUserAgent
: The User-Agent header to use for all requestsVPC_ID
: The EC2 VPC ID
Usage
The Launch Instances module is an auxiliary module that can be loaded using the
use command. To run the module, only the AccessKeyId
, SecretAccessKey
, and
KEY_NAME
options are required.
msf > use auxiliary/admin/aws/aws_launch_instances
msf auxiliary(aws_launch_instances) > show options
Module options (auxiliary/admin/aws/aws_launch_instances):
Name Current Setting Required Description
---- --------------- -------- -----------
AMI_ID ami-1e299d7e yes The Amazon Machine Image (AMI) ID
AccessKeyId yes AWS access key
KEY_NAME admin yes The SSH key to be used for ec2-user
Proxies no A proxy chain of format type:host:port[,type:host:port][...]
RHOST ec2.us-west-2.amazonaws.com yes AWS region specific EC2 endpoint
Region us-west-2 yes The default region
SSH_PUB_KEY no The public SSH key to be used for ec2-user, e.g., "ssh-rsa ABCDE..."
SecretAccessKey yes AWS secret key
Token no AWS session token
USERDATA_FILE no The script that will be executed on start
msf auxiliary(aws_launch_instances) > set SecretAccessKey asdfasd+asdfasdfasd...
SecretAccessKey => asdfasd+asdfasdfasd...
msf auxiliary(aws_launch_instances) > set AccessKeyId AKIAAKIAAKIAAKIAAKIAA
AccessKeyId => AKIAJH47PFECK3EVTBKA
msf auxiliary(aws_launch_instances) > set KEY_NAME ec2-user-key
KEY_NAME => ec2-user-key
msf auxiliary(aws_launch_instances) > set SSH_PUB_KEY ssh-rsa ABCDEDG123...
SSH_PUB_KEY => ssh-rsa ABCDEDG123...
msf auxiliary(aws_launch_instances) > run
[*] Created ec2-user-key (ab:cd:ef:12:34:56:78:90:ab:ac:ad:ab:a1:23:45:67)
[*] Created security group: sg-12345678
[*] Launching instance(s) in us-west-2, AMI: ami-1e299d7e, key pair name: ec2-user, security group: sg-12345678, subnet ID: subnet-abcdefgh
[*] Launched instance i-12345678 in us-west-2 account 123456789012
[*] instance i-12345678 status: initializing
[*] instance i-12345678 status: initializing
...
[*] instance i-12345678 status: ok
[*] Instance i-12345678 has IP address 54.186.158.6
[*] Auxiliary module execution completed
When the host has passed its primary system checks, the IP address will be
displayed. We can use this IP address to SSH to the host. Please note that
most users will want to set the SEC_GROUP_CIDR
option to restrict access to
our new Cloud host.
To SSH into the host, you must specify the SSH key, and ec2-user username, e.g.,
$ ssh -i ec2-user-key ec2-user@54.186.158.6 -L 2447:127.0.0.1:2447
The authenticity of host '54.186.158.6 (54.186.158.6)' can't be established.
ECDSA key fingerprint is SHA256:ePj6WtCeK...
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '54.186.158.6' (ECDSA) to the list of known hosts.
__| __|_ )
_| ( / Amazon Linux AMI
___|\___|___|
https://aws.amazon.com/amazon-linux-ami/2016.09-release-notes/
5 package(s) needed for security, out of 9 available
Run "sudo yum update" to apply all updates.
[ec2-user@ip-172-31-8-176 ~]$
Back in the Metasploit console you can now connect via aggregator:
msf auxiliary(aws_launch_instances) > load aggregator
msf auxiliary(aws_launch_instances) > aggregator_connect 127.0.0.1:2447
[*] Connecting to Aggregator instance at 127.0.0.1:2447...
msf auxiliary(aws_launch_instances) >