AWS Root Account MFA

Severity: critical
Compliance: CIS 1.13; PCI 8.3, 8.4
Tags: AWS, Identity & Access Management, Privilege Escalation:Valid Accounts
Reference: https://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html
Source: github.com/panther-labs/panther-analysis

Validates that Multi-Factor Authentication (MFA) is enabled for the AWS root account. The root account has complete unrestricted access to all AWS resources and is the highest-value target for attackers. Without MFA, accounts are vulnerable to phishing, credential stuffing, and password compromise attacks.

MITRE ATT&CK coverage

Tactic	Techniques
Privilege Escalation	`T1078` Valid Accounts

Rule body yaml

AnalysisType: policy
Filename: aws_root_account_mfa.py
PolicyID: "AWS.RootAccount.MFA"
DisplayName: "AWS Root Account MFA"
Enabled: true
ResourceTypes:
  - AWS.IAM.RootUser
Tags:
  - AWS
  - Identity & Access Management
  - Privilege Escalation:Valid Accounts
Reports:
  CIS:
    - 1.13
  PCI:
    - 8.3
    - 8.4
  MITRE ATT&CK:
    - TA0004:T1078
Severity: Critical
Description: >
  Validates that Multi-Factor Authentication (MFA) is enabled for the AWS root account. The root account has complete unrestricted access to all AWS resources and is the highest-value target for attackers. Without MFA, accounts are vulnerable to phishing, credential stuffing, and password compromise attacks.
Runbook: |
  1. Query CloudTrail for ConsoleLogin events where userIdentity.type equals "Root" in the past 90 days to identify when the root account was last used and assess the risk window without MFA
  2. Sign in to AWS Console as root, navigate to Security Credentials, assign an MFA device (Virtual MFA, Hardware TOTP, or FIDO security key), and test the MFA configuration by logging out and back in
  3. Store the root password and MFA device in separate secure locations, document the MFA device details, and implement AWS Organizations SCPs to monitor root account console logins
Reference: https://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html
Tests:
  - Name: MFA Enabled
    ExpectedResult: true
    Resource:
      {
        "ARN": "arn:aws:iam::123456789012:root",
        "CreateDate": "2019-01-01T00:00:00Z",
        "CredentialReport":
          {
            "ARN": "arn:aws:iam::123456789012:root",
            "AccessKey1Active": false,
            "AccessKey1LastRotated": "0001-01-01T00:00:00Z",
            "AccessKey1LastUsedDate": "0001-01-01T00:00:00Z",
            "AccessKey1LastUsedRegion": "N/A",
            "AccessKey1LastUsedService": "N/A",
            "AccessKey2Active": false,
            "AccessKey2LastRotated": "0001-01-01T00:00:00Z",
            "AccessKey2LastUsedDate": "0001-01-01T00:00:00Z",
            "AccessKey2LastUsedRegion": "N/A",
            "AccessKey2LastUsedService": "N/A",
            "Cert1Active": false,
            "Cert1LastRotated": "0001-01-01T00:00:00Z",
            "Cert2Active": false,
            "Cert2LastRotated": "0001-01-01T00:00:00Z",
            "MfaActive": true,
            "PasswordEnabled": false,
            "PasswordLastChanged": "0001-01-01T00:00:00Z",
            "PasswordLastUsed": "2019-01-01T00:00:00Z",
            "PasswordNextRotation": "0001-01-01T00:00:00Z",
            "UserCreationTime": "2019-01-01T00:00:00Z",
            "UserName": "<root_account>",
          },
        "UserID": null,
        "UserName": "root",
        "VirtualMFA": null,
      }
  - Name: MFA Not Enabled
    ExpectedResult: false
    Resource:
      {
        "ARN": "arn:aws:iam::123456789012:root",
        "CreateDate": "2019-01-01T00:00:00Z",
        "CredentialReport":
          {
            "ARN": "arn:aws:iam::123456789012:root",
            "AccessKey1Active": false,
            "AccessKey1LastRotated": "0001-01-01T00:00:00Z",
            "AccessKey1LastUsedDate": "0001-01-01T00:00:00Z",
            "AccessKey1LastUsedRegion": "N/A",
            "AccessKey1LastUsedService": "N/A",
            "AccessKey2Active": false,
            "AccessKey2LastRotated": "0001-01-01T00:00:00Z",
            "AccessKey2LastUsedDate": "0001-01-01T00:00:00Z",
            "AccessKey2LastUsedRegion": "N/A",
            "AccessKey2LastUsedService": "N/A",
            "Cert1Active": false,
            "Cert1LastRotated": "0001-01-01T00:00:00Z",
            "Cert2Active": false,
            "Cert2LastRotated": "0001-01-01T00:00:00Z",
            "MfaActive": false,
            "PasswordEnabled": false,
            "PasswordLastChanged": "0001-01-01T00:00:00Z",
            "PasswordLastUsed": "2019-01-01T00:00:00Z",
            "PasswordNextRotation": "0001-01-01T00:00:00Z",
            "UserCreationTime": "2019-01-01T00:00:00Z",
            "UserName": "<root_account>",
          },
        "UserID": null,
        "UserName": "root",
        "VirtualMFA": null,
      }

Detection logic

Condition

CredentialReport.MfaActive not eq "True"

Exclusions

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

Field	Kind	Excluded values
`CredentialReport.MfaActive`	eq	`True`

`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)