ModifyInstanceAttribute
AWS
ModifyInstanceAttribute
Event
Modifies a specific attribute of an EC2 instance, such as its instance type, user data, or security groups.
Security Context
- Command execution capabilities can be leveraged by adversaries to run arbitrary scripts and tools within the cloud environment.
- Impairing defenses allows adversaries to operate freely by removing security controls that would otherwise detect or block their activity.
Log Source
CloudTrail
Sample Event
Adversarial — execution. Draco modifies the user-data of i-0occamy0000000001 (the OCCAMY pipeline EC2 he previously stole credentials from) to inject a bash payload that adds his SSH key to authorized_keys and runs a reverse shell. The instance was already stopped (a prerequisite — userData cannot be modified while running); next he’ll call StartInstances to trigger execution. T1685 + T1059.
{ "eventVersion": "1.09", "userIdentity": { "type": "IAMUser", "principalId": "AIDADRAC0MALF0YBADGY", "arn": "arn:aws:iam::555123456789:user/draco", "accountId": "555123456789", "accessKeyId": "ASIADRAC0MALF0YEXAMP5", "userName": "draco", "sessionContext": { "attributes": { "creationDate": "2026-04-15T21:42:08Z", "mfaAuthenticated": "false" } } }, "eventTime": "2026-04-15T22:48:51Z", "eventSource": "ec2.amazonaws.com", "eventName": "ModifyInstanceAttribute", "awsRegion": "us-east-1", "sourceIPAddress": "203.0.113.66", "userAgent": "aws-cli/1.18.147 Python/3.7.10 Linux/5.4.0-1045-aws botocore/1.18.6", "requestParameters": { "instanceId": "i-0occamy0000000001", "userData": { "value": "<sensitiveDataRemoved>" } }, "responseElements": { "requestId": "90000000-0000-4000-8000-000101010110", "_return": true }, "requestID": "90000000-0000-4000-8000-000101010110", "eventID": "90000000-0000-4000-8000-000101010111", "readOnly": false, "eventType": "AwsApiCall", "managementEvent": true, "recipientAccountId": "555123456789", "eventCategory": "Management", "tlsDetails": { "tlsVersion": "TLSv1.3", "cipherSuite": "TLS_AES_128_GCM_SHA256", "clientProvidedHostHeader": "ec2.us-east-1.amazonaws.com" }}MITRE ATT&CK Mapping
Tactics: Defense Impairment Execution
Techniques:
- T1578 — Modify Cloud Compute Infrastructure — An adversary may attempt to modify a cloud account's compute service infrastructure to evade defenses. A modification to the compute service infrastructure can include the creation, deletion, or modification of one or more components such as compute instances, virtual machines, and snapshots.
- T1059 — Command and Scripting Interpreter — Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries. These interfaces and languages provide ways of interacting with computer systems and are a common feature across many different platforms. Most systems come with some built-in command-line interface a...