This search provides specific SAML access from specific Service Provider, user and targeted principal at AWS. This search provides specific information to detect abnormal access or potential credential hijack or forgery, specially in federated environments using SAML protocol inside the perimeter or cloud provider.
- Type: Anomaly
Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Last Updated: 2021-01-26
- Author: Rod Soto, Splunk
- ID: bbe23980-6019-11eb-ae93-0242ac130002
Kill Chain Phase
1 2 3 4 5 `cloudtrail` eventName=Assumerolewithsaml | stats count min(_time) as firstTime max(_time) as lastTime by requestParameters.principalArn requestParameters.roleArn requestParameters.roleSessionName recipientAccountId responseElements.issuer sourceIPAddress userAgent | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` |`aws_saml_access_by_provider_user_and_principal_filter`
The SPL above uses the following Macros:
aws_saml_access_by_provider_user_and_principal_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
List of fields required to use this analytic.
How To Implement
You must install splunk AWS add on and Splunk App for AWS. This search works with AWS CloudTrail logs
Known False Positives
Attacks using a Golden SAML or SAML assertion hijacks or forgeries are very difficult to detect as accessing cloud providers with these assertions looks exactly like normal access, however things such as source IP sourceIPAddress user, and principal targeted at receiving cloud provider along with endpoint credential access and abuse detection searches can provide the necessary context to detect these attacks.
Associated Analytic Story
|64.0||80||80||From IP address $sourceIPAddress$, user agent $userAgent$ has trigged an event $eventName$ for account ID $recipientAccountId$|
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
source | version: 1