Awesome
AWS Lambda - IAM Access Key Disabler
The AWS Key disabler is a Lambda Function that disables AWS IAM User Access Keys after a set amount of time in order to reduce the risk associated with old access keys.
AWS Lambda Architecture
SysOps Output for EndUser
Developer Toolchain
Current Limitations
- A report containing the output (json) of scan will be sent to a single defined sysadmin account, refer to the
report_to
attribute in the/grunt/package.json
build configuration file. - Keys are only disabled, not deleted nor replaced
Prerequisites
This script requires the following components to run.
- Node.js with NPM installed https://nodejs.org/en/
- Gruntjs installed http://gruntjs.com/
- AWSCLI commandline tool installed https://aws.amazon.com/cli/
It also assumes that you have an AWS account with SES enabled, ie domain verified and sandbox mode removed.
Installation instructions
These instructions are for OSX. Your mileage may vary on Windows and other *nix.
- Grab yourself a copy of this script
- Navigate into the
/grunt
folder - Setup the Grunt task runner, e.g. install its deps:
npm install
- Fill in the following information in
/grunt/package.json
- Set the
aws_account_number
value to your AWS account id found on https://portal.aws.amazon.com/gp/aws/manageYourAccount - Set the
first_warning
andlast_warning
to the age that the key has to be in days to trigger a warning. These limits trigger an email send toreport_to
- Set the
expiry
to the age in days when the key expires. At this age the key is disabled and an email is triggered toreport_to
notifying this change - Set the
serviceaccount
to the account username you want the script to ignore - Set the
exclusiongroup
to the name of a group assigned to users you want the script to ignore. - Set the
send_completion_report
value toTrue
to enable email delivery via SES - Set the
report_to
value to the email address you'd like to receive deletion reports to - Set the
report_from
value to the email address you'd like to use as the sender address for deletion reports. Note that the domain for this needs to be verified in AWS SES. - Set the
deployment_region
to a region that supports Lambda. 10 Set theemail_region
to the region that supports SES. Also ensure that the region has SES sandbox mode disabled.- See the AWS Region table for support https://aws.amazon.com/about-aws/global-infrastructure/regional-product-services/
- Set the
- Ensure you can successfully connect to AWS from the CLI, eg run
aws iam get-user
to verify successful connection - from the
/grunt
directory rungrunt bumpup && grunt deployLambda
to bump your version number and perform a build/deploy of the Lambda function to the selected region
Invoke the Lambda Function manually from the commandline using the AWSCLI
Execute the lambda function by name, AccessKeyRotation
, logging the output of the scan to a file called scan.report.log
:
aws lambda invoke --function-name AccessKeyRotation scan.report.log --region us-east-1
{
"StatusCode": 200
}
Use jq
to render the contents of the scan.report.log
to the console:
jq '.' scan.report.log
{
"reportdate": "2016-06-26 10:37:24.071091",
"users": [
{
"username": "TestS3User",
"userid": "1",
"keys": [
{
"age": 72,
"changed": false,
"state": "key is already in an INACTIVE state",
"accesskeyid": "**************Q3GA1"
},
{
"age": 12,
"changed": false,
"state": "key is still young",
"accesskeyid": "**************F3AA2"
}
]
},
{
"username": "BlahUser22",
"userid": "2",
"keys": []
},
{
"username": "LambdaFake1",
"userid": "3",
"keys": [
{
"age": 23,
"changed": false,
"state": "key is due to expire in 1 week (7 days)",
"accesskeyid": "**************DFG12"
},
{
"age": 296,
"changed": false,
"state": "key is already in an INACTIVE state",
"accesskeyid": "**************4ZASD"
}
]
},
{
"username": "apiuser49",
"userid": "4",
"keys": [
{
"age": 30,
"changed": true,
"state": "key is now EXPIRED! Changing key to INACTIVE state",
"accesskeyid": "**************ER2E2"
},
{
"age": 107,
"changed": false,
"state": "key is already in an INACTIVE state",
"accesskeyid": "**************AWQ4K"
}
]
},
{
"username": "UserEMRKinesis",
"userid": "5",
"keys": [
{
"age": 30,
"changed": false,
"state": "key is now EXPIRED! Changing key to INACTIVE state",
"accesskeyid": "**************MGB41A"
}
]
},
{
"username": "CDN-Drupal",
"userid": "6",
"keys": [
{
"age": 10,
"changed": false,
"state": "key is still young",
"accesskeyid": "**************ZDSQ5A"
},
{
"age": 5,
"changed": false,
"state": "key is still young",
"accesskeyid": "**************E3ODA"
}
]
},
{
"username": "ChocDonutUser1",
"userid": "7",
"keys": [
{
"age": 59,
"changed": false,
"state": "key is already in an INACTIVE state",
"accesskeyid": "**************CSA123"
}
]
},
{
"username": "ChocDonut2",
"userid": "8",
"keys": [
{
"age": 60,
"changed": false,
"state": "key is already in an INACTIVE state",
"accesskeyid": "**************FDGD2"
}
]
},
{
"username": "admin.skynet@cyberdyne.systems.com",
"userid": "9",
"keys": [
{
"age": 45,
"changed": false,
"state": "key is already in an INACTIVE state",
"accesskeyid": "**************BLQ5GJ"
},
{
"age": 71,
"changed": false,
"state": "key is already in an INACTIVE state",
"accesskeyid": "**************GJFF53"
}
]
}
]
}
Additional configuration option
- You can choose to set the message used for each warning and the final disabling by changing the values under
key_disabler.keystates.<state>.message
- You can change the length of masking under
key_disabler.mask_accesskey_length
. The access keys are 20 characters in length.
Troubleshooting
This script is provided as is. We are happy to answer questions as time allows but can't give any promises.
If things don't work ensure that:
- You can authenticate successfully against AWS using the AWSCLI commandline tool
- SES is not in sandbox mode and the sender domain has been verified
- The selected region provides both Lambda and SES https://aws.amazon.com/about-aws/global-infrastructure/regional-product-services/
Bonus Points
Once the Lambda Function has been successfully deployed - the following commands can be performed:
aws lambda list-functions
openssl dgst -binary -sha256 ..\Releases\AccessKeyRotationPackage.1.0.18.zip | openssl base64
aws lambda invoke --function-name AccessKeyRotation report.log --region us-east-1
jq '.' report.log
jq '.users[] | select(.username=="johndoe")' report.log
jq '.' report.log | grep age | cut -d':' -f2 | sort -n
Bonus Bonus Points
jq 'def maximal_by(f): (map(f) | max) as $mx | .[] | select(f == $mx); .users | maximal_by(.keys[].age)' report.log
jq 'def minimal_by(f): (map(f) | min) as $mn | .[] | select(f == $mn); .users | minimal_by(.keys[].age)' report.log