Cloud Instance Metadata API
Where this stands
No Sigma rule can address this — the telemetry MITRE names has no Sigma logsource behind it.
None of MITRE's analytics for this technique name a log source that maps to a Sigma logsource — they describe abstract data ("Process::None"), API-hook telemetry, or prose channels with no reliable field names behind them.
What the technique is
Adversaries may attempt to access the Cloud Instance Metadata API to collect credentials and other sensitive data. Most cloud service providers support a Cloud Instance Metadata API which is a service provided to running virtual instances that allows applications to access information about the running virtual instance. Available information generally includes name, security group, and additional metadata including sensitive data such as credentials and UserData scripts that may contain additional secrets. The Instance Metadata API is provided as a convenience to assist in managing applications and is accessible by anyone who can access the instance. A cloud metadata API has been used in at least one high profile compromise. If adversaries have a presence on the running virtual instance, they may query the Instance Metadata API directly to identify credentials that grant access to additional resources. Additionally, adversaries may exploit a Server-Side Request Forgery (SSRF) vulnerability in a public facing web proxy that allows them to gain access to the sensitive information via a request to the Instance Metadata API. The de facto standard across cloud service providers is to host the Instance Metadata API at http[:]//169.254.169.254.
Read it on attack.mitre.orgWhat MITRE says you would watch
- AN0001
Detects access attempts to cloud instance metadata endpoints (e.g., 169.254.169.254) from virtual machines or containerized workloads. This includes both direct access and SSRF exploitation patterns.
Technique names and descriptions © MITRE ATT&CK®, CC BY 4.0. Not endorsed by MITRE.