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s3tk：一款针对Amazon S3的安全审计套件

 4 years ago
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s3tk是一款针对Amazon S3的安全审计套件，广大安全研究人员可以使用s3tk来对Amazon S3 Bucket进行安全测试。

FBJJB3v.jpg!web

工具安装

广大研究人员可以使用pip来完成s3tk的安装：

pip install s3tk

研究人员可以使用AWS CLI命令行工具来配置AWS凭证：

pip install awscli
aws configure

工具使用命令

安全扫描

可扫描的Bucket组件如下：

1、公开ACL
2、公开策略
3、屏蔽的公开访问
4、启用的登录
5、版本修改
6、默认加密

s3tk scan

针对特定Bucket运行扫描：

s3tk scan my-bucket my-bucket-2

支持通配符：

s3tk scan "my-bucket*"

跳过日志和默认加密：

s3tk scan --skip-logging --skip-versioning --skip-default-encryption

获取邮件通知（通过SNS）：

s3tk scan --sns-topic arn:aws:sns:...

枚举策略

枚举Bucket策略：

s3tk list-policy

针对特定Bucket运行扫描：

s3tk list-policy my-bucket my-bucket-2

显示名称：

s3tk list-policy --named

设置策略：

s3tk set-policy my-bucket --no-object-acl

删除策略：

s3tk delete-policy my-bucket

屏蔽公开访问：

s3tk block-public-access my-bucket my-bucket-2

启用默认加密

针对所有Bucket启用默认加密：

s3tk enable-default-encryption

仅针对特定Bucket启用：

s3tk enable-default-encryption my-bucket my-bucket-2

扫描对象ACL

扫描目标Bucket中所有对象的ACL：

s3tk scan-object-acl my-bucket

扫描特定对象：

s3tk scan-object-acl my-bucket --only "*.pdf"

排除特定对象：

s3tk scan-object-acl my-bucket --except "*.jpg"

扫描DNS 

s3tk scan-dns

凭证

用户凭证可以在“~/.aws/credentials”中或环境变量中设置，我们可以使用下列命令设置一个profile：

AWS_PROFILE=your-profile s3tk

IAM策略

下面给出的是每一条命令所需的权限，用户只需要将相应权限在下列代码中声明即可：

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "Scan",
            "Effect": "Allow",
            "Action": [
                "s3:ListAllMyBuckets",
                "s3:GetBucketAcl",
                "s3:GetBucketPolicy",
                "s3:GetBucketPublicAccessBlock",
                "s3:GetBucketLogging",
                "s3:GetBucketVersioning",
                "s3:GetEncryptionConfiguration"
            ],
            "Resource": "*"
        },
        {
            "Sid": "ScanDNS",
            "Effect": "Allow",
            "Action": [
                "s3:ListAllMyBuckets",
                "route53:ListHostedZones",
                "route53:ListResourceRecordSets"
            ],
            "Resource": "*"
        },
        {
            "Sid": "ListPolicy",
            "Effect": "Allow",
            "Action": [
                "s3:ListAllMyBuckets",
                "s3:GetBucketPolicy"
            ],
            "Resource": "*"
        },
        {
            "Sid": "SetPolicy",
            "Effect": "Allow",
            "Action": [
                "s3:PutBucketPolicy"
            ],
            "Resource": "*"
        },
        {
            "Sid": "DeletePolicy",
            "Effect": "Allow",
            "Action": [
                "s3:DeleteBucketPolicy"
            ],
            "Resource": "*"
        },
        {
            "Sid": "BlockPublicAccess",
            "Effect": "Allow",
            "Action": [
                "s3:ListAllMyBuckets",
                "s3:PutBucketPublicAccessBlock"
            ],
            "Resource": "*"
        },
        {
            "Sid": "EnableLogging",
            "Effect": "Allow",
            "Action": [
                "s3:ListAllMyBuckets",
                "s3:PutBucketLogging"
            ],
            "Resource": "*"
        },
        {
            "Sid": "EnableVersioning",
            "Effect": "Allow",
            "Action": [
                "s3:ListAllMyBuckets",
                "s3:PutBucketVersioning"
            ],
            "Resource": "*"
        },
        {
            "Sid": "EnableDefaultEncryption",
            "Effect": "Allow",
            "Action": [
                "s3:ListAllMyBuckets",
                "s3:PutEncryptionConfiguration"
            ],
            "Resource": "*"
        },
        {
            "Sid": "ResetObjectAcl",
            "Effect": "Allow",
            "Action": [
                "s3:ListBucket",
                "s3:GetObjectAcl",
                "s3:PutObjectAcl"
            ],
            "Resource": [
                "arn:aws:s3:::my-bucket",
                "arn:aws:s3:::my-bucket/*"
            ]
        },
        {
            "Sid": "Encrypt",
            "Effect": "Allow",
            "Action": [
                "s3:ListBucket",
                "s3:GetObject",
                "s3:PutObject"
            ],
            "Resource": [
                "arn:aws:s3:::my-bucket",
                "arn:aws:s3:::my-bucket/*"
            ]
        },
        {
            "Sid": "DeleteUnencryptedVersions",
            "Effect": "Allow",
            "Action": [
                "s3:ListBucketVersions",
                "s3:GetObjectVersion",
                "s3:DeleteObjectVersion"
            ],
            "Resource": [
                "arn:aws:s3:::my-bucket",
                "arn:aws:s3:::my-bucket/*"
            ]
        }
    ]
}

访问日志

Amazon Athena适用于查询S3日志，创建下列表：

CREATE EXTERNAL TABLE my_bucket (
    bucket_owner string,
    bucket string,
    time string,
    remote_ip string,
    requester string,
    request_id string,
    operation string,
    key string,
    request_verb string,
    request_url string,
    request_proto string,
    status_code string,
    error_code string,
    bytes_sent string,
    object_size string,
    total_time string,
    turn_around_time string,
    referrer string,
    user_agent string,
    version_id string
)
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.RegexSerDe'
WITH SERDEPROPERTIES (
    'serialization.format' = '1',
    'input.regex' = '([^ ]*) ([^ ]*) \\[(.*?)\\] ([^ ]*) ([^ ]*) ([^ ]*) ([^ ]*) ([^ ]*) \\\"([^ ]*) ([^ ]*) (- |[^ ]*)\\\" (-|[0-9]*) ([^ ]*) ([^ ]*) ([^ ]*) ([^ ]*) ([^ ]*) ([^ ]*) (\"[^\"]*\\") ([^ ]*)$'
) LOCATION 's3://my-s3-logs/my-bucket/';

修改最后一行代码，并指向你的日志Bucket：

SELECT
    date_parse(time, '%d/%b/%Y:%H:%i:%S +0000') AS time,
    request_url,
    remote_ip,
    user_agent
FROM
    my_bucket
WHERE
    requester = '-'
    AND status_code LIKE '2%'
    AND request_url LIKE '/some-keys%'
ORDER BY 1

CloudTrail日志

Amazon Athena同样可以用于查询CloudTrail日志，创建一个表：

CREATE EXTERNAL TABLE cloudtrail_logs (
    eventversion STRING,
    userIdentity STRUCT<
        type:STRING,
        principalid:STRING,
        arn:STRING,
        accountid:STRING,
        invokedby:STRING,
        accesskeyid:STRING,
        userName:String,
        sessioncontext:STRUCT<
            attributes:STRUCT<
                mfaauthenticated:STRING,
                creationdate:STRING>,
            sessionIssuer:STRUCT<
                type:STRING,
                principalId:STRING,
                arn:STRING,
                accountId:STRING,
                userName:STRING>>>,
    eventTime STRING,
    eventSource STRING,
    eventName STRING,
    awsRegion STRING,
    sourceIpAddress STRING,
    userAgent STRING,
    errorCode STRING,
    errorMessage STRING,
    requestId  STRING,
    eventId  STRING,
    resources ARRAY<STRUCT<
        ARN:STRING,
        accountId:STRING,
        type:STRING>>,
    eventType STRING,
    apiVersion  STRING,
    readOnly BOOLEAN,
    recipientAccountId STRING,
    sharedEventID STRING,
    vpcEndpointId STRING,
    requestParameters STRING,
    responseElements STRING,
    additionalEventData STRING,
    serviceEventDetails STRING
)
ROW FORMAT SERDE 'com.amazon.emr.hive.serde.CloudTrailSerde'
STORED  AS INPUTFORMAT 'com.amazon.emr.cloudtrail.CloudTrailInputFormat'
OUTPUTFORMAT 'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat'
LOCATION  's3://my-cloudtrail-logs/'

修改最后一行代码，并指向你的CloudTrail日志Bucket：

SELECT
    eventTime,
    eventName,
    userIdentity.userName,
    requestParameters
FROM
    cloudtrail_logs
WHERE
    eventName LIKE '%Bucket%'
ORDER BY 1

Bucket策略 

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Deny",
            "Principal": "*",
            "Action": "s3:PutObjectAcl",
            "Resource": "arn:aws:s3:::my-bucket/*"
        }
    ]
}

工具更新

运行下列命令：

pip install s3tk --upgrade

使用Master，可运行下列命令：

pip install git+https://github.com/ankane/s3tk.git --upgrade

Docker运行

运行下列命令：

docker run -it ankane/s3tk aws configure

提交你的凭证：

docker commit $(docker ps -l -q) my-s3tk

接下来，运行下列命令：

docker run -it my-s3tk s3tk scan

工具运行截图

EfQjeiZ.gif


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