Comandos de Resumo DFIR

Comando aws-ct-summary

Este comando cria um resumo das seguintes informações com base nos ARNs dos usuários: - Número total de eventos (chamadas de API) (NumOfEvents) - Timestamp da primeira chamada de API encontrada nos logs (FirstTimestamp) - Timestamp da última chamada de API encontrada nos logs (LastTimestamp) - Chamadas de API comumente abusadas que tiveram sucesso (AbusedAPIs-Success) - Chamadas de API comumente abusadas que foram tentadas mas falharam (AbusedAPIs-Failed) - Outras chamadas de API que não estão na lista de chamadas de API comumente abusadas que tiveram sucesso (OtherAPIs-Success) - Outras chamadas de API que não estão na lista de chamadas de API comumente abusadas que foram tentadas mas falharam (OtherAPIs-Failed) - Regiões da AWS onde as chamadas de API foram feitas (AWS-Regions) - Endereços IP de origem da chamada de API (SrcIPs) - Tipos de usuário (UserTypes) - IDs de chave de acesso de usuário (UserAccessKeyIDs) - User agents da origem que fez a chamada de API (UserAgents)

※ Observação: as chamadas de API que são comumente abusadas vêm do arquivo de configuração hospedado em https://github.com/Yamato-Security/suzaku-rules/blob/main/config/abused_aws_api_calls.csv. Este arquivo será atualizado ao longo do tempo e será sincronizado localmente toda vez que você executar o comando update-rules.

Estes resultados têm como objetivo fornecer aos analistas informações para descobrir contas comprometidas ou ataques que não dependem de assinaturas específicas. Por exemplo, você pode verificar se determinados usuários estão fazendo chamadas de API suspeitas que não deveriam estar fazendo, usando regiões que normalmente não são utilizadas, fazendo login a partir de endereços IP de origem suspeitos ou com user agents suspeitos, etc... Depois de encontrar quaisquer chamadas de API suspeitas sendo feitas, endereços IP de origem ou user agents, você pode determinar rapidamente quais chaves de acesso podem ter sido abusadas durante aquele período e pivotar nessas palavras-chave nos logs JSON originais para criar uma linha do tempo da atividade do atacante.

Aviso: haverá muitos dados nas células e provavelmente não serão exibidos adequadamente em programas como o Excel. Use o Numbers em um Mac, o Timeline Explorer no Windows, etc...

Exemplo de AbusedAPIs-Success:

Unique APIs: 11 | Total APIs 477,373
415,552 - RunInstances (ec2.amazonaws.com) - Spin up EC2 instances (crypto mining, tools) (2019-08-23 06:00:07 ~ 2019-08-23 06:00:07)
28,907 - GetBucketAcl (s3.amazonaws.com) - S3 recon (2019-08-21 08:03:03 ~ 2019-10-21 13:59:40)
10,095 - GetCallerIdentity (sts.amazonaws.com) - Current credentials recon (2019-08-23 06:00:07 ~ 2019-08-23 06:04:14)
9,936 - ListBuckets (s3.amazonaws.com) - S3 recon (2019-08-23 06:00:07 ~ 2019-08-23 06:14:53)
9,168 - DescribeInstances (ec2.amazonaws.com) - EC2 and network layout recon (2019-08-23 06:00:07 ~ 2019-08-23 06:04:20)
3,658 - DescribeVpcs (ec2.amazonaws.com) - EC2 and network layout recon (2019-08-21 08:03:03 ~ 2019-09-12 20:00:44)
19 - ListGroups (greengrass.amazonaws.com) - IAM enumeration (2019-08-21 08:03:03 ~ 2019-10-19 23:49:25)
14 - DescribeInstances (opsworks.amazonaws.com) - EC2 and network layout recon (2019-08-21 08:03:03 ~ 2019-10-19 23:49:22)
12 - GetBucketPolicy (s3.amazonaws.com) - S3 recon (2019-01-08 20:30:01 ~ 2020-03-29 09:06:56)
7 - ListGroups (resource-groups.amazonaws.com) - IAM enumeration (2019-01-08 20:30:01 ~ 2020-03-29 09:06:56)
5 - StartInstances (ec2.amazonaws.com) - Spin up EC2 instances (crypto mining, tools) (2019-08-21 08:03:03 ~ 2019-12-12 07:07:31)

Exemplo de AbusedAPIs-Failed:

Unique APIs: 23 | Total APIs 20,464
11,603 - AssumeRole (sts.amazonaws.com) - Lateral movement via roles (2019-08-21 08:03:03 ~ 2019-09-18 07:04:12)
7,279 - GetBucketAcl (s3.amazonaws.com) - S3 recon (2019-08-21 08:03:03 ~ 2019-09-09 09:01:26)
515 - GetBucketPolicy (s3.amazonaws.com) - S3 recon (2019-08-21 08:03:03 ~ 2019-10-01 19:11:07)
331 - ListUsers (iam.amazonaws.com) - IAM enumeration (2019-08-21 08:03:03 ~ 2019-08-29 14:53:14)
210 - ListSecrets (secretsmanager.amazonaws.com) - Find credential storage locations (2019-08-21 08:03:03 ~ 2019-10-19 23:49:30)
153 - ListGroups (iam.amazonaws.com) - IAM enumeration (2019-08-21 08:03:03 ~ 2019-09-12 15:24:39)
148 - ListRoles (iam.amazonaws.com) - IAM enumeration (2019-08-21 08:03:03 ~ 2019-09-12 15:20:56)
112 - ListAccessKeys (iam.amazonaws.com) - Enumerates keys on IAM users (2019-08-21 08:03:03 ~ 2019-09-16 14:28:15)
31 - ListGroups (greengrass.amazonaws.com) - IAM enumeration (2019-08-21 08:03:03 ~ 2020-02-25 14:41:24)
...

Exemplo de OtherAPIs-Success:

Unique APIs: 289 | Total APIs 143,759
98,689 - DescribeSnapshots (ec2.amazonaws.com) (2019-08-23 06:00:07 ~ 2019-08-23 06:50:59)
10,679 - DescribeSpotPriceHistory (ec2.amazonaws.com) (2019-08-21 08:03:03 ~ 2019-09-12 20:07:32)
3,740 - DescribeReservedInstancesOfferings (ec2.amazonaws.com) (2019-08-21 08:03:03 ~ 2019-09-12 20:07:30)
2,372 - DescribeSnapshotAttribute (ec2.amazonaws.com) (2019-08-21 08:03:03 ~ 2019-08-24 12:38:34)
2,307 - CreateDefaultVpc (ec2.amazonaws.com) (2019-08-23 06:00:07 ~ 2019-08-23 06:04:17)
1,532 - DescribeKeyPairs (ec2.amazonaws.com) (2019-08-23 06:00:07 ~ 2019-08-23 06:04:16)
1,504 - DescribeSecurityGroups (ec2.amazonaws.com) (2019-08-21 08:03:03 ~ 2019-09-12 20:00:40)
1,495 - DescribeImages (ec2.amazonaws.com) (2019-08-21 08:03:03 ~ 2019-09-12 20:07:26)
1,438 - CreateKeyPair (ec2.amazonaws.com) (2019-08-23 06:00:07 ~ 2019-08-23 06:04:16)
1,402 - DescribeVolumes (ec2.amazonaws.com) (2019-08-21 08:03:03 ~ 2019-09-03 12:06:20)
1,217 - DescribeSubnets (ec2.amazonaws.com) (2019-08-21 08:03:03 ~ 2019-09-12 20:00:43)
...

Exemplo de AWS-Regions:

Total regions: 16
167,155 - us-west-2 (2019-08-23 06:00:07 ~ 2019-08-23 06:14:53)
113,328 - us-east-1 (2019-08-23 06:00:07 ~ 2019-08-23 06:04:14)
65,718 - ap-northeast-2 (2019-08-23 06:00:07 ~ 2019-08-23 06:22:55)
64,787 - ap-northeast-1 (2019-08-23 06:00:07 ~ 2019-08-23 06:34:57)
...

Exemplo de SrcIPs:

Total source IPs: 5,293
634,454 - 5.205.62.253 (2019-08-23 06:00:07 ~ 2019-08-23 06:00:07)
23,498 - 193.29.252.218 (2019-08-21 08:03:00 ~ 2019-10-17 09:11:22)
15,925 - 155.63.17.217 (2018-04-17 10:09:00 ~ 2020-09-21 21:06:22)
9,067 - 253.0.255.253 (2018-04-17 10:09:00 ~ 2020-09-21 21:06:22)
7,078 - 163.21.250.220 (2018-04-17 10:09:00 ~ 2020-09-21 21:06:22)
6,575 - 236.9.245.88 (2018-04-17 10:09:00 ~ 2020-09-21 21:06:22)
5,138 - 84.252.252.117 (2019-01-08 20:30:01 ~ 2020-03-29 09:06:56)
4,946 - 24.251.252.2 (2019-08-21 08:03:00 ~ 2019-09-30 06:36:13)
4,225 - 211.111.151.81 (2019-08-21 08:03:00 ~ 2019-09-12 19:53:35)
...

Exemplo de UserType:

IAMUser

Exemplo de UserAccessKeyIDs:

Total access key ids: 629
667,476 - AKIA01U43UX3RBRDXF4Q (2019-08-23 06:00:07 ~ 2019-08-23 06:00:07)
218,544 - ASIARF55FBMFZBXLKDFW (2019-08-21 11:31:47 ~ 2019-08-23 13:00:28)
12,677 - AKIA1ZBTOEKWKVHP6GHZ (2017-02-12 21:15:12 ~ 2020-09-21 21:06:22)
8,822 - ASIAGD2JRX0V6RJGWR59 (2018-04-17 10:09:00 ~ 2020-09-21 21:06:22)
4,940 - ASIAUNHV6EHIK5MNPEKF (2019-08-21 08:03:00 ~ 2019-09-30 06:36:17)
...

Observe que, como haverá uma grande quantidade de IDs temporários de chave de acesso do AWS STS, estes são filtrados por padrão. Adicione a opção -s, --include-sts-keys se quiser incluí-los.

Exemplo de UserAgents:

Total user agents: 7,760
351,022 - Boto3/1.9.201 Python/2.7.12 Linux/4.4.0-159-generic Botocore/1.12.201 (2019-08-23 06:00:07 ~ 2019-08-23 06:00:07)
283,430 - Boto3/1.9.201 Python/2.7.12 Linux/4.4.0-157-generic Botocore/1.12.201 (2019-08-21 11:31:47 ~ 2019-08-23 13:00:28)
23,467 - [Boto3/1.15.13 Python/3.8.5 Darwin/19.6.0 Botocore/1.18.13 Resource] (2017-02-12 21:15:12 ~ 2020-10-07 16:05:52)
15,924 - Boto3/1.7.4 Python/2.7.12 Linux/4.4.0-119-generic Botocore/1.10.4 (2018-04-17 10:09:00 ~ 2020-09-21 21:06:22)
9,400 - aws-sdk-java/1.11.301 Linux/4.9.93-linuxkit-aufs Java_HotSpot(TM)_64-Bit_Server_VM/25.172-b11 java/1.8.0_172 (2018-04-17 10:09:00 ~ 2020-09-21 21:06:22)
6,372 - [Boto3/1.7.65 Python/3.5.2 Linux/4.13.0-37-generic Botocore/1.10.65 Resource] (2018-04-17 10:09:00 ~ 2020-09-21 21:06:22)
5,352 - AWSPowerShell/3.3.365.0 .NET_Runtime/4.0 .NET_Framework/4.0 OS/Microsoft_Windows_NT_10.0.01985.0 WindowsPowerShell/5.0 ClientSync (2019-01-08 20:30:01 ~ 2020-03-29 09:06:56)
4,945 - Boto3/1.9.231 Python/2.7.15+ Linux/4.15.0-64-generic Botocore/1.12.231 (2019-08-21 08:03:00 ~ 2019-09-30 06:36:13)
4,599 - [aws-cli/1.16.301 Python/3.7.6 Linux/5.4.0-kali3-amd64 botocore/1.13.37] (2019-08-21 08:03:00 ~ 2020-02-09 22:00:32)
3,909 - Boto3/1.14.28 Python/3.8.5 Linux/5.7.0-kali1-amd64 Botocore/1.17.28 (2019-01-08 20:30:01 ~ 2020-09-11 17:35:39)
3,450 - Boto3/1.4.2 Python/2.7.13+ Linux/4.9.0-3-amd64 Botocore/1.5.19 (2017-02-12 21:15:12 ~ 2020-09-21 21:06:22)
3,198 - Boto3/1.4.2 Python/2.7.14 Linux/4.13.0-1-amd64 Botocore/1.5.19 (2017-02-12 21:15:12 ~ 2020-09-21 21:06:22)
...

Observe que a ferramenta cliente aws incluirá as informações do SO no user agent, então é possível detectar se houve chamadas de API feitas a partir de SOs de atacantes como o kali.

Uso do comando

Usage:
  suzaku aws-ct-summary <INPUT> [OPTIONS]

Input:
  -d, --directory <DIR>  Directory of multiple gz/json files
  -f, --file <FILE>      File path to one gz/json file

Filtering:
      --timeline-start <DATE>  Start time of the events to load (ex: "2022-02-22T23:59:59Z)
      --timeline-end <DATE>    End time of the events to load (ex: "2020-02-22T00:00:00Z")
      --time-offset <OFFSET>   Scan recent events based on an offset (ex: 1y, 3M, 30d, 24h, 30m)
  -s, --include-sts-keys       Include temporary AWS STS access key IDs

Output:
  -o, --output <FILE>           Output results to a CSV file
  -D, --hide-descriptions       Hide description of the commonly abused API calls
  -G, --GeoIP <MAXMIND-DB-DIR>  Add GeoIP (ASN, city, country) info to IP addresses

Display Settings:
  -K, --no-color  Disable color output
  -q, --quiet     Quiet mode: do not display the launch banner

General Options:
  -h, --help  Show the help menu

Exemplo do comando aws-ct-metrics

• Salvar resultados em um arquivo CSV: ./suzaku aws-ct-summary -d ../suzaku-sample-data -o sample-summary.csv