version: 1.0.1
requiredDataConnectors:
- connectorId: AWS
dataTypes:
- AWSCloudTrail
status: Available
entityMappings:
- fieldMappings:
- identifier: Name
columnName: AccountName
- identifier: UPNSuffix
columnName: AccountUPNSuffix
- identifier: CloudAppAccountId
columnName: RecipientAccountId
entityType: Account
- fieldMappings:
- identifier: Address
columnName: SourceIpAddress
entityType: IP
tactics:
- DefenseEvasion
relevantTechniques:
- T1562
queryFrequency: 1h
severity: High
name: Successful brute force attack on S3 Bucket.
description: |
'A successful brute force attack on an S3 bucket was detected. Verify these actions, and if needed, remediate the compromise.'
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_S3BruteForce.yaml
query: |
let timeframe = 1h;
let failed_attempts = AWSCloudTrail
| where TimeGenerated >= ago(timeframe)
| where EventName == "GetObject" and isnotempty(ErrorMessage) and isnotempty(ErrorCode)
| where UserIdentityAccountId == "ANONYMOUS_PRINCIPAL" or UserIdentityAccessKeyId <> RecipientAccountId
| extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)
| extend UserName = tostring(split(UserIdentityArn, '/')[-1])
| extend AccountName = case( UserIdentityPrincipalid == "Anonymous", "Anonymous", isempty(UserIdentityUserName), UserName, UserIdentityUserName)
| extend AccountName = iif(AccountName contains "@", tostring(split(AccountName, '@', 0)[0]), AccountName),
AccountUPNSuffix = iif(AccountName contains "@", tostring(split(AccountName, '@', 1)[0]), "")
| extend bucketName = tostring(parse_json(RequestParameters).bucketName), keyName = tostring(parse_json(RequestParameters).key)
| summarize time_min_failed=arg_min(TimeGenerated, *), failed_keys = dcount(keyName) by RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId, SourceIpAddress, bucketName
| where failed_keys > 20;
let success_attempts = AWSCloudTrail
| where TimeGenerated >= ago(timeframe)
| where EventName == "GetObject" and isempty(ErrorMessage) and isempty(ErrorCode)
| where UserIdentityAccountId == "ANONYMOUS_PRINCIPAL" or UserIdentityAccessKeyId <> RecipientAccountId
| extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)
| extend UserName = tostring(split(UserIdentityArn, '/')[-1])
| extend AccountName = case( UserIdentityPrincipalid == "Anonymous", "Anonymous", isempty(UserIdentityUserName), UserName, UserIdentityUserName)
| extend AccountName = iif(AccountName contains "@", tostring(split(AccountName, '@', 0)[0]), AccountName),
AccountUPNSuffix = iif(AccountName contains "@", tostring(split(AccountName, '@', 1)[0]), "")
| extend bucketName = tostring(parse_json(RequestParameters).bucketName), keyName = tostring(parse_json(RequestParameters).key)
| summarize time_min_success=arg_min(TimeGenerated, *), success_keys = dcount(keyName) by RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId, SourceIpAddress, bucketName
| where success_keys >= 1;
failed_attempts
| join kind=inner success_attempts on SourceIpAddress, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId, bucketName
| where time_min_success > time_min_failed
| project-away keyName
| extend timestamp = time_min_success
kind: Scheduled
queryPeriod: 1h
triggerOperator: gt
id: 31b9e94b-0df6-4a3d-a297-3457b53c5d86
