AWS EC2 Manual Security Group Change

Severity: medium
Group by: requestParameters
Entities: aws_account_ids, aws_arns, ip_addresses
Log types: AWS.CloudTrail
Tags: AWS, Security Control, Configuration Required, Defense Evasion:Impair Defenses
Reference: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/working-with-security-groups.html
Source: github.com/panther-labs/panther-analysis

An EC2 security group was manually updated without abiding by the organization's accepted processes. This rule expects organizations to either use the Console, CloudFormation, or Terraform, configurable in the rule's ALLOWED_USER_AGENTS.

MITRE ATT&CK coverage

Tactic	Techniques
Stealth	`T1562` Impair Defenses

Rules detecting the same action

Other rules on this platform that filter on the same API call or operation.

AWSCloudTrail - Changes to AWS Security Group ingress and egress settings (Kusto)
EC2 Security Group Modified (Panther)

Rule body yaml

AnalysisType: rule
Filename: aws_ec2_manual_security_group_changes.py
RuleID: "AWS.EC2.ManualSecurityGroupChange"
DisplayName: "AWS EC2 Manual Security Group Change"
Enabled: false
LogTypes:
  - AWS.CloudTrail
Reports:
  MITRE ATT&CK:
    - TA0005:T1562
Tags:
  - AWS
  - Security Control
  - Configuration Required
  - Defense Evasion:Impair Defenses
Severity: Medium
Description: >
  An EC2 security group was manually updated without abiding by the organization's accepted processes. This rule expects organizations to either use the Console, CloudFormation, or Terraform, configurable in the rule's ALLOWED_USER_AGENTS.
Runbook: Identify the actor who changed the security group and validate it was legitimate
Reference: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/working-with-security-groups.html
Tests:
  - Name: AWS Console - Ingress SG Authorization
    LogType: AWS.CloudTrail
    ExpectedResult: true
    Log:
      {
        "awsRegion": "us-west-2",
        "eventID": "504b492f-7832-406b-a4fd-45a13e48adc4",
        "eventName": "AuthorizeSecurityGroupIngress",
        "eventSource": "ec2.amazonaws.com",
        "eventTime": "2021-01-24 04:55:45.000",
        "eventType": "AwsApiCall",
        "eventVersion": "1.08",
        "managementEvent": true,
        "readOnly": false,
        "recipientAccountId": "112233445566",
        "requestID": "91f34d65-513d-4e9f-a3de-e8d27f7ee4b2",
        "requestParameters":
          {
            "groupId": "sg-04f0b44316f7d2471",
            "ipPermissions":
              {
                "items":
                  [
                    {
                      "ipRanges": { "items": [{ "cidrIp": "0.0.0.0/16" }] },
                      "prefixListIds": {},
                      "fromPort": "443",
                      "toPort": "443",
                      "groups": {},
                      "ipProtocol": "tcp",
                      "ipv6Ranges": {},
                    },
                  ],
              },
          },
        "responseElements":
          {
            "_return": true,
            "requestId": "91f34d65-513d-4e9f-a3de-e8d27f7ee4b2",
          },
        "sourceIPAddress": "136.25.37.134",
        "userAgent": "console.ec2.amazonaws.com",
        "userIdentity":
          {
            "type": "AssumedRole",
            "principalid": "ARORJ4ULULLE0EEJAAKDO:alan",
            "arn": "arn:aws:sts::112233445566:assumed-role/TestAdmin/alan",
            "accountid": "112233445566",
            "accesskeyid": "ASIASWJRT64Z7ZLFLJNI",
            "sessioncontext":
              {
                "attributes":
                  {
                    "mfaauthenticated": "true",
                    "creationdate": "2021-01-24T04:55:10Z",
                  },
                "sessionissuer":
                  {
                    "type": "Role",
                    "principalid": "ARORJ4ULULLE0EEJAAKDO",
                    "arn": "arn:aws:iam::112233445566:role/TestAdmin",
                    "accountid": "112233445566",
                    "username": "TestAdmin",
                  },
              },
          },
        "p_event_time": "2021-01-24 04:55:45.000",
        "p_parse_time": "2021-01-24 05:02:58.358",
        "p_log_type": "AWS.CloudTrail",
        "p_row_id": "1a57ff7ade26aaf5a1a4d7d20775",
        "p_source_id": "e55677c6-7ef5-4541-a443-0d0f17eec19f",
        "p_source_label": "CloudTrail Test",
        "p_any_ip_addresses": ["136.25.37.134"],
        "p_any_aws_account_ids": ["112233445566"],
        "p_any_aws_arns":
          [
            "arn:aws:iam::112233445566:role/TestAdmin",
            " arn:aws:sts::112233445566:assumed-role/TestAdmin/alan",
          ],
      }
  - Name: Terraform Security Group Creation
    LogType: AWS.CloudTrail
    ExpectedResult: false
    Log:
      {
        "eventVersion": "1.05",
        "userIdentity":
          {
            "type": "AssumedRole",
            "principalId": "AROAIZCYMDBM4SJU6XXXX:ryan@example.com",
            "arn": "arn:aws:sts::112233445566:assumed-role/Operator/ryan@example.com",
            "accountId": "112233445566",
            "accessKeyId": "ASIAWDWBPTM3RJH7XXXX",
            "sessionContext":
              {
                "sessionIssuer":
                  {
                    "type": "Role",
                    "principalId": "AROAIZCYMDBM4SJU65M54",
                    "arn": "arn:aws:iam::112233445566:role/Operator",
                    "accountId": "112233445566",
                    "userName": "Operator",
                  },
                "webIdFederationData": {},
                "attributes":
                  {
                    "mfaAuthenticated": "false",
                    "creationDate": "2020-04-30T23:50:12Z",
                  },
              },
          },
        "eventTime": "2020-04-30T23:51:06Z",
        "eventSource": "ec2.amazonaws.com",
        "eventName": "CreateSecurityGroup",
        "awsRegion": "us-east-1",
        "sourceIPAddress": "100.1.114.142",
        "userAgent": "aws-sdk-go/1.29.7 (go1.13.7; darwin; amd64) APN/1.0 HashiCorp/1.0 Terraform/0.12.24 (+https://www.terraform.io)",
        "requestParameters":
          {
            "groupName": "prod-webapp-webserver-security",
            "groupDescription": "prod-webapp-webserver Security SG",
            "vpcId": "vpc-a1a044c7",
          },
        "responseElements":
          {
            "requestId": "594fe3e3-0f74-4085-9336-189b36a1cd8c",
            "_return": true,
            "groupId": "sg-04d018d184a18f647",
          },
        "requestID": "594fe3e3-0f74-4085-9336-189b36a1cd8c",
        "eventID": "52601748-2659-4ed8-b5fd-c530547b07ec",
        "eventType": "AwsApiCall",
        "recipientAccountId": "112233445566",
      }
  - Name: Terraform Security Group Authorize Egress
    LogType: AWS.CloudTrail
    ExpectedResult: false
    Log:
      {
        "eventVersion": "1.05",
        "userIdentity":
          {
            "type": "AssumedRole",
            "principalId": "AROAIZCYMDBM4SJU65M54:ryan@example.com",
            "arn": "arn:aws:sts::112233445566:assumed-role/ContinousDeployment/ryan@example.com",
            "accountId": "112233445566",
            "accessKeyId": "ASIAWDWBPTM3RJH7XXXX",
            "sessionContext":
              {
                "sessionIssuer":
                  {
                    "type": "Role",
                    "principalId": "AROAIZCYMDBM4SJU65M54",
                    "arn": "arn:aws:iam::112233445566:role/Operator",
                    "accountId": "112233445566",
                    "userName": "Operator",
                  },
                "webIdFederationData": {},
                "attributes":
                  {
                    "mfaAuthenticated": "false",
                    "creationDate": "2020-04-30T23:50:12Z",
                  },
              },
          },
        "eventTime": "2020-04-30T23:51:08Z",
        "eventSource": "ec2.amazonaws.com",
        "eventName": "AuthorizeSecurityGroupEgress",
        "awsRegion": "us-east-1",
        "sourceIPAddress": "100.1.114.142",
        "userAgent": "aws-sdk-go/1.29.7 (go1.13.7; darwin; amd64) APN/1.0 HashiCorp/1.0 Terraform/0.12.24 (+https://www.terraform.io)",
        "requestParameters":
          {
            "groupId": "sg-03eee825d6bb78f54",
            "ipPermissions":
              {
                "items":
                  [
                    {
                      "ipProtocol": "-1",
                      "groups": {},
                      "ipRanges":
                        {
                          "items":
                            [
                              {
                                "cidrIp": "0.0.0.0/0",
                                "description": "Allow egress to the internet. Required for now until we land ECS/ECR endpoints in the VPC",
                              },
                            ],
                        },
                      "ipv6Ranges": {},
                      "prefixListIds": {},
                    },
                  ],
              },
          },
        "responseElements":
          {
            "requestId": "4c7a5036-09d3-46e8-b0b6-f611ff1959a6",
            "_return": true,
          },
        "requestID": "4c7a5036-09d3-46e8-b0b6-f611ff1959a6",
        "eventID": "1a593035-e072-49c4-8c72-4ff35e195330",
        "eventType": "AwsApiCall",
        "recipientAccountId": "112233445566",
      }
  - Name: Go Script Authorize Ingress
    LogType: AWS.CloudTrail
    ExpectedResult: true
    Log:
      {
        "eventVersion": "1.05",
        "userIdentity":
          {
            "type": "AssumedRole",
            "principalId": "AROAIZCYMDBM4SJU65M54:ryan@example.com",
            "arn": "arn:aws:sts::112233445566:assumed-role/Operator/ryan@example.com",
            "accountId": "112233445566",
            "accessKeyId": "ASIAWDWBPTM3QPXQXXXX",
            "sessionContext":
              {
                "sessionIssuer":
                  {
                    "type": "Role",
                    "principalId": "AROAIZCYMDBM4SJU65M54",
                    "arn": "arn:aws:iam::112233445566:role/Operator",
                    "accountId": "112233445566",
                    "userName": "Operator",
                  },
                "webIdFederationData": {},
                "attributes":
                  {
                    "mfaAuthenticated": "false",
                    "creationDate": "2020-04-30T04:37:13Z",
                  },
              },
          },
        "eventTime": "2020-04-30T04:40:52Z",
        "eventSource": "ec2.amazonaws.com",
        "eventName": "AuthorizeSecurityGroupIngress",
        "awsRegion": "us-east-1",
        "sourceIPAddress": "100.1.114.142",
        "userAgent": "aws-sdk-go/1.24.1 (go1.14; darwin; amd64)",
        "requestParameters":
          {
            "groupId": "sg-0d921df5d84f7270a",
            "ipPermissions":
              {
                "items":
                  [
                    {
                      "ipProtocol": "tcp",
                      "fromPort": 22,
                      "toPort": 22,
                      "groups": {},
                      "ipRanges": { "items": [{ "cidrIp": "0.0.0.0/0" }] },
                      "ipv6Ranges": {},
                      "prefixListIds": {},
                    },
                  ],
              },
          },
        "responseElements":
          {
            "requestId": "2be70b99-4937-4a76-b7d9-390b6d0eda73",
            "_return": true,
          },
        "requestID": "2be70b99-4937-4a76-b7d9-390b6d0eda73",
        "eventID": "42155429-7e8e-43b5-9b5e-6953f80d51d5",
        "eventType": "AwsApiCall",
        "recipientAccountId": "112233445566",
      }
  - Name: AWS Console - Ingress SG Authorization Error
    LogType: AWS.CloudTrail
    ExpectedResult: false
    Log:
      {
        "awsRegion": "us-west-2",
        "errorCode": "UnauthorizedOperation",
        "eventID": "504b492f-7832-406b-a4fd-45a13e48adc4",
        "eventName": "AuthorizeSecurityGroupIngress",
        "eventSource": "ec2.amazonaws.com",
        "eventTime": "2021-01-24 04:55:45.000",
        "eventType": "AwsApiCall",
        "eventVersion": "1.08",
        "managementEvent": true,
        "readOnly": false,
        "recipientAccountId": "112233445566",
        "requestID": "91f34d65-513d-4e9f-a3de-e8d27f7ee4b2",
        "requestParameters":
          {
            "groupId": "sg-04f0b44316f7d2471",
            "ipPermissions":
              {
                "items":
                  [
                    {
                      "ipRanges": { "items": [{ "cidrIp": "0.0.0.0/16" }] },
                      "prefixListIds": {},
                      "fromPort": "443",
                      "toPort": "443",
                      "groups": {},
                      "ipProtocol": "tcp",
                      "ipv6Ranges": {},
                    },
                  ],
              },
          },
        "responseElements":
          {
            "_return": true,
            "requestId": "91f34d65-513d-4e9f-a3de-e8d27f7ee4b2",
          },
        "sourceIPAddress": "136.25.37.134",
        "userAgent": "console.ec2.amazonaws.com",
        "userIdentity":
          {
            "type": "AssumedRole",
            "principalid": "ARORJ4ULULLE0EEJAAKDO:alan",
            "arn": "arn:aws:sts::112233445566:assumed-role/TestAdmin/alan",
            "accountid": "112233445566",
            "accesskeyid": "ASIASWJRT64Z7ZLFLJNI",
            "sessioncontext":
              {
                "attributes":
                  {
                    "mfaauthenticated": "true",
                    "creationdate": "2021-01-24T04:55:10Z",
                  },
                "sessionissuer":
                  {
                    "type": "Role",
                    "principalid": "ARORJ4ULULLE0EEJAAKDO",
                    "arn": "arn:aws:iam::112233445566:role/TestAdmin",
                    "accountid": "112233445566",
                    "username": "TestAdmin",
                  },
              },
          },
        "p_event_time": "2021-01-24 04:55:45.000",
        "p_parse_time": "2021-01-24 05:02:58.358",
        "p_log_type": "AWS.CloudTrail",
        "p_row_id": "1a57ff7ade26aaf5a1a4d7d20775",
        "p_source_id": "e55677c6-7ef5-4541-a443-0d0f17eec19f",
        "p_source_label": "CloudTrail Test",
        "p_any_ip_addresses": ["136.25.37.134"],
        "p_any_aws_account_ids": ["112233445566"],
        "p_any_aws_arns":
          [
            "arn:aws:iam::112233445566:role/TestAdmin",
            " arn:aws:sts::112233445566:assumed-role/TestAdmin/alan",
          ],
      }

Detection logic

Condition

not (errorCode is_not_null or errorMessage is_not_null)
eventName in ["CreateSecurityGroup", "AuthorizeSecurityGroupIngress", "AuthorizeSecurityGroupEgress"]
recipientAccountId in ["11111111111111", "112233445566"]
not (userAgent wildcard "* HashiCorp/?.0 Terraform/*" and (userIdentity.arn contains "Operator" or userIdentity.arn contains "ContinousDeployment"))

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

Field	Kind	Excluded values
`userIdentity.arn`	contains	`ContinousDeployment`
`userIdentity.arn`	contains	`Operator`
`userAgent`	match	`HashiCorp/?.0 Terraform/`
`errorCode`	is_not_null	(no value, null check)
`errorMessage`	is_not_null	(no value, null check)

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`eventName`	in	`AuthorizeSecurityGroupEgress` `AuthorizeSecurityGroupIngress` `CreateSecurityGroup`
`recipientAccountId`	in	`11111111111111` `112233445566`

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

Field
`eventName`
`eventSource`
`awsRegion`
`recipientAccountId`
`sourceIPAddress`
`userAgent`
`userIdentity`

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)