def run(arguments=''):
args = parse_args(arguments)
if args.html:
HTMLReport(args.output).save()
if args.verbose:
print(f'HTML report saved to {args.output}/report.html')
exit(0)
rmtree(args.output, ignore_errors=True)
Path(args.output).mkdir(parents=True, exist_ok=True)
configure_log(args.output)
identity = STS(f'arn:aws:sts:{args.region}', args.profile, args.keys[0],
args.keys[1]).identity
if args.verbose:
print(header, end='\n\n')
for _ in ['UserId', 'Account', 'Arn']:
align(_, identity[_], orange)
print('')
statistics = Statistics(args.output)
visibility = VisibilityReport(args.output)
for arn in get_functions(args):
if arnparse(arn):
arn = arnparse(arn)
if args.verbose:
count = '[' + f'{statistics.statistics["lambdas"]+1}'.rjust(
4, ' ') + '] '
print(f'\r{green}{count}{arn.resource}{nocolor}'.ljust(
100, ' '),
end='')
lmbd = Lambda(arn.full, args)
statistics.parse(lmbd.report())
visibility.save(lmbd.report())
SecurityReport(args.output).save()
HTMLReport(args.output).save()
if args.verbose:
print('\r' + ' ' * 100, end='\r') # clear
align('Lambdas', statistics.statistics["lambdas"])
align('Security', statistics.statistics["security"]["count"])
align('Triggers', statistics.statistics["triggers"]["count"])
align('Resources', statistics.statistics["resources"]["count"])
align('Layers', statistics.statistics["layers"])
align('Runtimes', len(statistics.statistics["runtimes"]["items"]))
align('Regions', len(statistics.statistics["regions"]["items"]))
align('Report', f'{args.output}/report.html')
print('\n')
def get_triggers(self):
'''
Tracks events that trigger the Lambda function
'''
# Collect triggers from Event Sources
try:
eventSource = self.client.list_event_source_mappings(
FunctionName=self.arn.resource)['EventSourceMappings']
for event in eventSource:
if event['State'] != 'Enabled':
continue
self.triggers['items'][event['EventSourceArn']] = [
'lambda:InvokeFunction'
]
# Track services
self.triggers['services'].append(
arnparse(event['EventSourceArn']).service)
except Exception:
debug(self.arn.full)
# Collect triggers from Function policy
try:
if self.policy:
for statement in self.policy['Statement']:
if 'Condition' in statement:
if 'ArnLike' in statement['Condition']:
if 'AWS:SourceArn' in statement['Condition'][
'ArnLike']:
arn = statement['Condition']['ArnLike'][
'AWS:SourceArn']
if type(statement['Action']) == str:
self.triggers['items'][arn] = [
statement['Action']
]
else:
self.triggers['items'][arn] = statement[
'Action']
# Track services
self.triggers['services'].append(
arnparse(arn).service)
except Exception:
debug(self.arn.full)
self.triggers['services'] = list(set(self.triggers['services']))
def get_triggers(self):
"""
Tracks events that trigger the Lambda function
"""
# Collect triggers from Event Sources
try:
eventSource = self.client.list_event_source_mappings(
FunctionName=self.arn.resource)["EventSourceMappings"]
for event in eventSource:
if event["State"] != "Enabled":
continue
self.triggers["items"][event["EventSourceArn"]] = [
"lambda:InvokeFunction"
]
# Track services
self.triggers["services"].append(
arnparse(event["EventSourceArn"]).service)
except Exception:
debug(self.arn.full)
# Collect triggers from Function policy
try:
if self.policy:
for statement in self.policy["Statement"]:
if "Condition" in statement:
if "ArnLike" in statement["Condition"]:
if "AWS:SourceArn" in statement["Condition"][
"ArnLike"]:
arn = statement["Condition"]["ArnLike"][
"AWS:SourceArn"]
if type(statement["Action"]) == str:
self.triggers["items"][arn] = [
statement["Action"]
]
else:
self.triggers["items"][arn] = statement[
"Action"]
# Track services
self.triggers["services"].append(
arnparse(arn).service)
except Exception:
debug(self.arn.full)
self.triggers["services"] = list(set(self.triggers["services"]))
def __init__(self,
arn,
profile=None,
access_key_id=None,
secret_access_key=None):
# AWS ARN
self.arn = arnparse(arn)
# AWS Profile and Keys
self.profile = profile
self.access_key_id = access_key_id
self.secret_access_key = secret_access_key
# AWS Resource-based policy
self.policy = {}
# Additional service information
self.info = ''
# AWS connection
session = boto3.Session(profile_name=self.profile)
self.client = session.client(self.arn.service,
region_name=self.arn.region,
aws_access_key_id=access_key_id,
aws_secret_access_key=secret_access_key)
def test_arnparse_apigateway(self):
arn_str = 'arn:aws:execute-api:us-east-1:0:api-id/stage/verb/path'
arn = arnparse(arn_str)
self.assertEqual(arn.service, 'apigateway')
self.assertEqual(arn.resource_type, 'api-id')
self.assertEqual(arn.resource, 'stage/verb/path')
arn_str = 'arn:aws:execute-api:*:*:*'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, '*')
self.assertEqual(arn.resource, '')
arn_str = 'arn:aws:execute-api:us-east-1:*:api-id/stage/*'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, 'api-id')
self.assertEqual(arn.resource, 'stage/*')
def test_arnparse_apigateway(self):
arn_str = "arn:aws:execute-api:us-east-1:0:api-id/stage/verb/path"
arn = arnparse(arn_str)
self.assertEqual(arn.service, "apigateway")
self.assertEqual(arn.resource_type, "api-id")
self.assertEqual(arn.resource, "stage/verb/path")
arn_str = "arn:aws:execute-api:*:*:*"
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, "*")
self.assertEqual(arn.resource, "")
arn_str = "arn:aws:execute-api:us-east-1:*:api-id/stage/*"
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, "api-id")
self.assertEqual(arn.resource, "stage/*")
def __init__(self,
arn,
profile=None,
access_key_id=None,
secret_access_key=None):
super().__init__(arn, profile, access_key_id, secret_access_key)
self.caller = self.get_caller_identity()
self.arn = arnparse(self.caller['Arn'])
self.acl = ACL(self.caller['Arn'])
def test_arnparse_lambda(self):
arn_str = "arn:aws:lambda:eu-west-1:0:function:function-name"
arn = arnparse(arn_str)
self.assertEqual(arn.full, arn_str)
self.assertEqual(arn.partition, "aws")
self.assertEqual(arn.service, "lambda")
self.assertEqual(arn.region, "eu-west-1")
self.assertEqual(arn.account_id, "0")
self.assertEqual(arn.resource_type, "function")
self.assertEqual(arn.resource, "function-name")
def test_arnparse_lambda(self):
arn_str = 'arn:aws:lambda:eu-west-1:0:function:function-name'
arn = arnparse(arn_str)
self.assertEqual(arn.full, arn_str)
self.assertEqual(arn.partition, 'aws')
self.assertEqual(arn.service, 'lambda')
self.assertEqual(arn.region, 'eu-west-1')
self.assertEqual(arn.account_id, '0')
self.assertEqual(arn.resource_type, 'function')
self.assertEqual(arn.resource, 'function-name')
def __init__(self, arn, profile=None, access_key_id=None, secret_access_key=None):
# Make sure we use IAM client
super().__init__("arn:aws:iam::", profile, access_key_id, secret_access_key)
self.arn = arnparse(arn)
self.policy_documents = []
self.permissions = []
if self.arn.resource_type == "user":
self.get_user_permissions()
elif self.arn.resource_type == "assumed-role":
self.get_role_permissions()
def test_arnparse_iam(self):
arn_str = "arn:aws:iam::0:role/service-role/role-name"
arn = arnparse(arn_str)
self.assertEqual(arn.full, arn_str)
self.assertEqual(arn.partition, "aws")
self.assertEqual(arn.service, "iam")
self.assertEqual(arn.region, None)
self.assertEqual(arn.account_id, "0")
self.assertEqual(arn.resource_type, "role/service-role")
self.assertEqual(arn.resource, "role-name")
arn_str = "arn:aws:iam::0:policy/service-role/role-name"
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, "policy/service-role")
self.assertEqual(arn.resource, "role-name")
arn_str = "arn:aws:iam::0:user/user-name"
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, "user")
self.assertEqual(arn.resource, "user-name")
def test_arnparse_iam(self):
arn_str = 'arn:aws:iam::0:role/service-role/role-name'
arn = arnparse(arn_str)
self.assertEqual(arn.full, arn_str)
self.assertEqual(arn.partition, 'aws')
self.assertEqual(arn.service, 'iam')
self.assertEqual(arn.region, None)
self.assertEqual(arn.account_id, '0')
self.assertEqual(arn.resource_type, 'role/service-role')
self.assertEqual(arn.resource, 'role-name')
arn_str = 'arn:aws:iam::0:policy/service-role/role-name'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, 'policy/service-role')
self.assertEqual(arn.resource, 'role-name')
arn_str = 'arn:aws:iam::0:user/user-name'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, 'user')
self.assertEqual(arn.resource, 'user-name')
def test_arnparse_to_dict(self):
arn_str = 'arn:aws:lambda:eu-west-1:0:function:function-name'
arn = arnparse(arn_str)
self.assertEqual(arn.to_dict(), {
'full': arn_str,
'partition': 'aws',
'service': 'lambda',
'region': 'eu-west-1',
'account_id': '0',
'resource_type': 'function',
'resource': 'function-name'
})
def test_arnparse_to_dict(self):
arn_str = "arn:aws:lambda:eu-west-1:0:function:function-name"
arn = arnparse(arn_str)
self.assertEqual(
arn.to_dict(),
{
"full": arn_str,
"partition": "aws",
"service": "lambda",
"region": "eu-west-1",
"account_id": "0",
"resource_type": "function",
"resource": "function-name",
},
)
def parse(self, report, verbose=False):
'''
Parses Lambda report and automatically extracts and
tracks statistics.
'''
self.statistics['lambdas'] += 1
self.track('regions', report['region'])
self.track('runtimes', report['runtime'])
for idx in ['triggers', 'resources']:
for arn in report[idx]['items']:
if arn == '*':
continue
self.track(idx, arnparse(arn).service)
if 'count' in report['security']:
for level, level_count in report['security']['count'].items():
self.track('security', level, level_count)
self.save(verbose=verbose)
def parse(self, report, verbose=False):
"""
Parses Lambda report and automatically extracts and
tracks statistics.
"""
self.statistics["lambdas"] += 1
self.statistics["layers"] += len(report["layers"])
self.track("regions", report["region"])
self.track("runtimes", report["runtime"])
for idx in ["triggers", "resources"]:
for arn in report[idx]["items"]:
if arn == "*":
continue
self.track(idx, arnparse(arn).service)
if "count" in report["security"]:
for level, level_count in report["security"]["count"].items():
self.track("security", level, level_count)
self.save(verbose=verbose)
def get_regions(args):
"""
Valid region specification:
Single: eu-west-1
Multiple: eu-west-1,ap-south-1,us-east-2
All: all
Returns regions as a Python list
"""
if not isinstance(args.region, str):
raise ValueError("No region specified")
if args.function:
return [arnparse(args.function).region]
available = boto3.Session().get_available_regions("lambda")
if args.region == "all":
return available
regions = args.region.split(",")
if not regions:
raise ValueError("No region specified")
for region in regions:
if region not in available:
raise ValueError(f'Invalid region "{region}"')
return regions
def test_arnparse_kms(self):
arn_str = 'arn:aws:kms:eu-west-1:0:key/key-id'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, 'key')
self.assertEqual(arn.resource, 'key-id')
def test_arnparse_s3(self):
arn_str = 'arn:aws:s3:::bucket-name'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, None)
self.assertEqual(arn.resource, 'bucket-name')
def test_arnparse_invalid(self):
with self.assertRaises(ValueError):
arnparse('')
with self.assertRaises(ValueError):
arnparse('arn:aws:service')
def test_arnparse_logs(self):
arn_str = 'arn:aws:logs:eu-west-1:0:log-group:/aws/lambda/function:*'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, 'log-group')
self.assertEqual(arn.resource, '/aws/lambda/function:*')
def test_arnparse_dynamodb(self):
arn_str = 'arn:aws:dynamodb:us-west-2:0:table/table-name'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, 'table')
self.assertEqual(arn.resource, 'table-name')
def audit(self):
if type(self.statement) != dict:
return None
if self.statement["Effect"] != "Allow":
return None
# Where
where = "in Policy Statement"
if self.policy:
where = f'in Role Policy {self.policy["name"]}'
elif "Sid" in self.statement:
where = f'{where} Sid {self.statement["Sid"]}'
# Principal
if self.is_unrestricted("Principal"):
if self.is_undefined("Condition"):
yield {
"level":
"high",
"text":
("Service is publicly accessible due to unrestricted "
f"Principal and undefined Condition {where}\n"
"https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_principal.html"
),
}
# NotPrincipal
if self.get("NotPrincipal"):
yield {
"level":
"high",
"text":
("Anonymous or unauthenticated users may have access to this "
f"service due to using NotPrincipal with Allow {where}\n"
"https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_notprincipal.html"
),
}
yield {
"level": "info",
"text": f"Use NotPrincipal with Deny {where}"
}
# Resource
if self.is_unrestricted("Resource"):
if self.is_unrestricted("Action"):
if self.is_undefined("Condition"):
yield {
"level":
"info",
"text":
("Service can perform any operation on any service due "
f"to unrestricted Resource, unrestricted Action and undefined Condition {where}"
),
}
elif self.is_undefined("Condition"):
operations = list(
set([x.split(":")[0] for x in self.get("Action")]))
for _ in operations:
if _ not in [
"sqs",
"s3",
"iam",
"sns",
"vpc",
"ec2",
"ecs",
"es",
"logs",
"dynamodb",
"kms",
"cloudformation",
]:
operations.pop(operations.index(_))
if len(operations):
yield {
"level":
"info",
"text":
(f'Service can perform {", ".join(operations)} operations on '
f"any service due to unrestricted Resource and undefined Condition {where}"
),
}
else:
for resource in self.get("Resource"):
arn = arnparse(resource)
if arn.account_id == "*":
yield {
"level":
"low",
"text":
f"Unrestricted AWS Account ID in {arn.service} {resource} {where}",
}
# Action
for action in self.get("Action"):
if action == "*" or action.split(":")[1] == "*":
yield {
"level":
"low",
"text":
(f"Unrestricted Action {action} {where}\n"
"https://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html#grant-least-privilege"
),
}
# NotAction
if self.get("NotAction"):
yield {
"level":
"medium",
"text":
(f"Users may have more permissions than intended due to using NotAction with Allow {where}\n"
"https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_notaction.html"
),
}
yield {"level": "info", "text": f"Use NotAction with Deny {where}"}
# Condition
if self.is_undefined("Condition"):
yield {
"level": "info",
"text": f"Use policy Conditions for extra security {where}",
}
# Managed vs Inline policies
if self.policy and self.policy["type"] == "inline":
yield {
"level":
"info",
"text":
f"Use Customer Managed policies instead of Inline policies {where}",
}
# Privilege Escalation via IAM permissions
yield from PrivilegeEscalation(self.get("Action")).audit()
def run(arguments=""):
"""
Main routine
"""
args = parse_args(arguments)
verbose(args, header, end="\n\n")
if args.html:
HTMLReport(args.output).save()
verbose(args, f"Generated {args.output}/report.html", end="\n\n")
exit(0)
rmtree(args.output, ignore_errors=True)
Path(args.output).mkdir(parents=True, exist_ok=True)
configure_log(args.output)
usage = get_usage(args)
verbose(args, "Loading identity")
region = list(usage.keys())[0]
sts_arn = f"arn:aws:sts:{region}"
identity = STS(sts_arn, args.profile, args.keys[0], args.keys[1])
if args.verbose:
for _ in ["UserId", "Account", "Arn"]:
align(_, identity.caller[_], orange)
print("")
statistics = Statistics(args.output)
visibility = VisibilityReport(args.output)
writes = LambdaWrite(args)
total_count = 0
for region_count in usage.values():
total_count += region_count
for region in usage.keys():
args.region = region
for arn_str in get_functions(args):
try:
arn = arnparse(arn_str)
counter = f'[ {statistics.statistics["lambdas"]+1}/{total_count} ] '
verbose(args, f"{counter}{arn.resource}")
lmbd = Lambda(arn.full, args, identity)
for w in writes.get_for_lambda(arn.full):
lmbd.set_writes(w)
statistics.parse(lmbd.report())
visibility.save(lmbd.report())
except Exception:
debug(arn_str)
SecurityReport(args.output).save()
HTMLReport(args.output).save()
if args.verbose:
print("\r" + " " * 100, end="\r") # clear
align("Lambdas", statistics.statistics["lambdas"])
align("Security", statistics.statistics["security"]["count"])
align("Triggers", statistics.statistics["triggers"]["count"])
align("Resources", statistics.statistics["resources"]["count"])
align("Layers", statistics.statistics["layers"])
align("Runtimes", len(statistics.statistics["runtimes"]["items"]))
align("Regions", len(statistics.statistics["regions"]["items"]))
print("")
align("Report", f"{args.output}/report.html")
align("Log", f"{args.output}/lambdaguard.log")
print("")
def scan(self):
'''
Scan Lambda report for vulnerabilities
and provide recommendations.
'''
# Audit Function policy
if not self.report['policy']['function']:
self.track(self.report['arn'], {
'level': 'info',
'text': 'Function policy is not defined'
})
else:
if 'Statement' in self.report['policy']['function']:
for statement in self.report['policy']['function'][
'Statement']:
for _ in PolicyStatement(statement).audit():
self.track(self.report['arn'], _)
# Audit Execution role policy
if not len(self.report['policy']['role']['policies']):
self.track(self.report['arn'], {
'level': 'info',
'text': 'Execution Role policy is not defined'
})
else:
for policy in self.report['policy']['role']['policies']:
if 'Statement' in policy['document']:
for statement in policy['document']['Statement']:
for _ in PolicyStatement(statement,
policy=policy).audit():
self.track(self.report['role'], _)
# Audit Resources
if 'logs' not in self.report['resources']['services']:
self.track(
self.report['arn'], {
'level':
'low',
'text':
'Function activity is not monitored by CloudWatch due to missing logs permissions'
})
# Audit Triggers and Resources
items = list(
set(
list(self.report['triggers']['items'].keys()) +
list(self.report['resources']['items'].keys())))
for arn in items:
if arn == '*':
continue
arn = arnparse(arn)
if arn.resource in ['*', '']:
continue
self.item = None
if arn.service == 's3':
if arn.resource_type: # S3 object path
continue
self.item = S3(arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key)
for _ in AccessControlList(self.item.acl).audit():
self.track(arn.full, _)
for _ in Encryption(self.item).audit():
self.track(arn.full, _)
elif arn.service == 'sqs':
self.item = SQS(arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key)
elif arn.service == 'sns':
self.item = SNS(arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key)
elif arn.service == 'apigateway':
self.item = APIGateway(
arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key)
elif arn.service == 'dynamodb':
self.item = DynamoDB(arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key)
if self.item:
# Audit item Resource-based Policy
if 'Statement' in self.item.policy:
for statement in self.item.policy['Statement']:
for _ in PolicyStatement(statement).audit():
self.track(arn.full, _)
# If policy is missing, the the service is public
else:
for _ in Public(self.item).audit():
self.track(arn.full, _)
# SonarQube
if self.args.sonarqube:
self.scan_sonarqube(arn, self.report['codeURL'],
self.report['runtime'])
for layer in self.report['layers']:
self.scan_sonarqube(arn, layer['codeURL'],
self.report['runtime'])
# Sort findings by level
sorted_items = []
for sort in ['high', 'medium', 'low', 'info']:
for item in self.security['items']:
if item['level'] == sort:
if item not in sorted_items:
sorted_items.append(item)
self.security['items'] = sorted_items
def test_arnparse_sqs(self):
arn_str = 'arn:aws:sqs:eu-west-1:0:queue-name'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, None)
self.assertEqual(arn.resource, 'queue-name')
def test_arnparse_sns(self):
arn_str = 'arn:aws:sns:us-east-1:0:topic-name'
arn = arnparse(arn_str)
self.assertEqual(arn.resource_type, None)
self.assertEqual(arn.resource, 'topic-name')
def scan(self):
"""
Scan Lambda report for vulnerabilities
and provide recommendations.
"""
# Audit Function policy
if not self.report["policy"]["function"]:
self.track(
self.report["arn"],
{
"level": "info",
"text": "Function policy is not defined"
},
)
else:
if "Statement" in self.report["policy"]["function"]:
for statement in self.report["policy"]["function"][
"Statement"]:
for _ in PolicyStatement(statement).audit():
self.track(self.report["arn"], _)
# Audit Execution role policy
if not len(self.report["policy"]["role"]["policies"]):
self.track(
self.report["arn"],
{
"level": "info",
"text": "Execution Role policy is not defined"
},
)
else:
for policy in self.report["policy"]["role"]["policies"]:
if "Statement" in policy["document"]:
for statement in policy["document"]["Statement"]:
for _ in PolicyStatement(statement,
policy=policy).audit():
self.track(self.report["role"], _)
# Audit KMS
if "kms" in self.report:
self.item = KMS(
self.report["kms"],
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key,
)
if not self.item.rotation:
self.track(
self.report["kms"],
{
"level":
"medium",
"text":
("Automatic rotation of key material is disabled\n"
"https://docs.aws.amazon.com/kms/latest/developerguide/rotate-keys.html"
),
},
)
for _, policy in self.item.policies.items():
self.audit_policy_statements(self.item.arn, policy)
# Audit Resources
if "logs" not in self.report["resources"]["services"]:
self.track(
self.report["arn"],
{
"level":
"low",
"text":
"Function activity is not monitored by CloudWatch due to missing logs permissions",
},
)
# Audit Triggers and Resources
items = list(
set(
list(self.report["triggers"]["items"].keys()) +
list(self.report["resources"]["items"].keys())))
for arn in items:
if arn == "*":
continue
arn = arnparse(arn)
if arn.resource in ["*", ""]:
continue
self.item = None
if arn.service == "s3":
if arn.resource_type: # S3 object path
continue
self.item = S3(
arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key,
)
for _ in AccessControlList(self.item.acl).audit():
self.track(arn.full, _)
for _ in Encryption(self.item).audit():
self.track(arn.full, _)
elif arn.service == "sqs":
self.item = SQS(
arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key,
)
elif arn.service == "sns":
self.item = SNS(
arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key,
)
elif arn.service == "apigateway":
self.item = APIGateway(
arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key,
)
elif arn.service == "dynamodb":
self.item = DynamoDB(
arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key,
)
elif arn.service == "kms":
self.item = KMS(
arn.full,
profile=self.profile,
access_key_id=self.access_key_id,
secret_access_key=self.secret_access_key,
)
if self.item:
if type(self.item) == KMS:
# Audit KMS Policies
for _, policy in self.item.policies.items():
self.audit_policy_statements(self.item.arn, policy)
else:
# Audit item Resource-based Policy
self.audit_policy_statements(self.item.arn,
self.item.policy)
# If policy is missing, then the service is public
for _ in Public(self.item).audit():
self.track(arn.full, _)
# SonarQube
if self.args.sonarqube:
self.scan_sonarqube(arn, self.report["codeURL"],
self.report["runtime"])
for layer in self.report["layers"]:
self.scan_sonarqube(arn, layer["codeURL"],
self.report["runtime"])
# Sort findings by level
sorted_items = []
for sort in ["high", "medium", "low", "info"]:
for item in self.security["items"]:
if item["level"] == sort:
if item not in sorted_items:
sorted_items.append(item)
self.security["items"] = sorted_items
def audit(self):
if self.statement['Effect'] != 'Allow':
return
# Where
where = 'in Policy Statement'
if self.policy:
where = f'in Role Policy {self.policy["name"]}'
elif 'Sid' in self.statement:
where = f'{where} Sid {self.statement["Sid"]}'
# Principal
if self.is_unrestricted('Principal'):
if self.is_undefined('Condition'):
yield {
'level':
'high',
'text':
f'Service is publicly accessible due to unrestricted Principal and undefined Condition {where}\nhttps://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_principal.html'
}
# NotPrincipal
if self.get('NotPrincipal'):
yield {
'level':
'high',
'text':
f'Anonymous or unauthenticated users may have access to this service due to using NotPrincipal with Allow {where}\nhttps://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_notprincipal.html'
}
yield {
'level': 'info',
'text': f'Use NotPrincipal with Deny {where}'
}
# Resource
if self.is_unrestricted('Resource'):
if self.is_unrestricted('Action'):
if self.is_undefined('Condition'):
yield {
'level':
'info',
'text':
f'Service can perform any operation on any service due to unrestricted Resource, unrestricted Action and undefined Condition {where}'
}
elif self.is_undefined('Condition'):
operations = list(
set([x.split(':')[0] for x in self.get('Action')]))
for _ in operations:
if _ not in [
'sqs', 's3', 'iam', 'sns', 'vpc', 'ec2', 'ecs',
'es', 'logs', 'dynamodb', 'kms', 'cloudformation'
]:
operations.pop(operations.index(_))
if len(operations):
yield {
'level':
'info',
'text':
f'Service can perform {", ".join(operations)} operations on any service due to unrestricted Resource and undefined Condition {where}'
}
else:
for resource in self.get('Resource'):
arn = arnparse(resource)
if arn.account_id == '*':
yield {
'level':
'low',
'text':
f'Unrestricted AWS Account ID in {arn.service} {resource} {where}'
}
# Action
for action in self.get('Action'):
if '*' in action:
yield {
'level':
'low',
'text':
f'Unrestricted Action {action} {where}\nhttps://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html#grant-least-privilege'
}
# NotAction
if self.get('NotAction'):
yield {
'level':
'medium',
'text':
f'Users may have more permissions than intended due to using NotAction with Allow {where}\nhttps://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_notaction.html'
}
yield {'level': 'info', 'text': f'Use NotAction with Deny {where}'}
# Condition
if self.is_undefined('Condition'):
yield {
'level': 'info',
'text': f'Use policy Conditions for extra security {where}'
}
# Managed vs Inline policies
if self.policy and self.policy['type'] == 'inline':
yield {
'level':
'info',
'text':
f'Use Customer Managed policies instead of Inline policies {where}'
}
# Privilege Escalation via IAM permissions
yield from PrivilegeEscalation(self.get('Action')).audit()
def run(arguments=''):
'''
Main routine
'''
args = parse_args(arguments)
verbose(args, header, end='\n\n')
if args.html:
HTMLReport(args.output).save()
verbose(args, f'Generated {args.output}/report.html', end='\n\n')
exit(0)
rmtree(args.output, ignore_errors=True)
Path(args.output).mkdir(parents=True, exist_ok=True)
configure_log(args.output)
usage = get_usage(args)
verbose(args, f'Loading identity')
region = list(usage.keys())[0]
sts_arn = f'arn:aws:sts:{region}'
identity = STS(sts_arn, args.profile, args.keys[0], args.keys[1])
if args.verbose:
for _ in ['UserId', 'Account', 'Arn']:
align(_, identity.caller[_], orange)
print('')
statistics = Statistics(args.output)
visibility = VisibilityReport(args.output)
writes = LambdaWrite(args)
total_count = 0
for region_count in usage.values():
total_count += region_count
for region in usage.keys():
args.region = region
for arn_str in get_functions(args):
try:
arn = arnparse(arn_str)
counter = f'[ {statistics.statistics["lambdas"]+1}/{total_count} ] '
verbose(args, f'{counter}{arn.resource}')
lmbd = Lambda(arn.full, args, identity)
for w in writes.get_for_lambda(arn.full):
lmbd.set_writes(w)
statistics.parse(lmbd.report())
visibility.save(lmbd.report())
except Exception:
debug(arn_str)
SecurityReport(args.output).save()
HTMLReport(args.output).save()
if args.verbose:
print('\r' + ' ' * 100, end='\r') # clear
align('Lambdas', statistics.statistics["lambdas"])
align('Security', statistics.statistics["security"]["count"])
align('Triggers', statistics.statistics["triggers"]["count"])
align('Resources', statistics.statistics["resources"]["count"])
align('Layers', statistics.statistics["layers"])
align('Runtimes', len(statistics.statistics["runtimes"]["items"]))
align('Regions', len(statistics.statistics["regions"]["items"]))
print('')
align('Report', f'{args.output}/report.html')
align('Log', f'{args.output}/lambdaguard.log')
print('')