AWS S3 Bucket Object Lock Configured

Severity: low
Compliance: PCI 10.5.3
Tags: AWS, S3, PCI, Impact:Data Destruction
Reference: https://docs.aws.amazon.com/AmazonS3/latest/dev/object-lock.html
Source: github.com/panther-labs/panther-analysis

This policy validates that S3 buckets have an Object Lock configuration enabled. This should be used with specific suppression lists to ensure it is applied only to appropriate S3 buckets, such as those containing CloudTrail or other auditable records.

MITRE ATT&CK coverage

Tactic	Techniques
Impact	`T1485` Data Destruction

Rule body yaml

AnalysisType: policy
Filename: aws_s3_bucket_object_lock_configured.py
PolicyID: "AWS.S3.BucketObjectLockConfigured"
DisplayName: "AWS S3 Bucket Object Lock Configured"
Enabled: false
ResourceTypes:
  - AWS.S3.Bucket
Tags:
  - AWS
  - S3
  - PCI
  - Impact:Data Destruction
Reports:
  PCI:
    - 10.5.3
  MITRE ATT&CK:
    - TA0040:T1485
Severity: Low
Description: >
  This policy validates that S3 buckets have an Object Lock configuration enabled. This should be used with specific suppression lists to ensure it is applied only to appropriate S3 buckets, such as those containing CloudTrail or other auditable records.
Runbook: Create a new S3 bucket with an appropriate Object Lock configuration and point audit records to that bucket.
Reference: https://docs.aws.amazon.com/AmazonS3/latest/dev/object-lock.html
Tests:
  - Name: Object Lock Configured With Governance
    ExpectedResult: false
    Resource:
      {
        "AccountId": "123456789012",
        "Arn": "arn:aws:s3:::example-bucket",
        "EncryptionRules":
          [
            {
              "ApplyServerSideEncryptionByDefault":
                { "KMSMasterKeyID": null, "SSEAlgorithm": "AES256" },
            },
          ],
        "Grants":
          [
            {
              "Grantee":
                {
                  "DisplayName": "example.user",
                  "EmailAddress": null,
                  "ID": "1",
                  "Type": "CanonicalUser",
                  "URI": null,
                },
              "Permission": "FULL_CONTROL",
            },
          ],
        "LifecycleRules": null,
        "LoggingPolicy": null,
        "MFADelete": "Disabled",
        "Name": "example-bucket",
        "ObjectLockConfiguration":
          {
            "ObjectLockEnabled": "Enabled",
            "Rule":
              {
                "DefaultRetention":
                  { "Days": 1, "Mode": "GOVERNANCE", "Years": null },
              },
          },
        "Owner": { "DisplayName": "example.user", "ID": "1" },
        "Policy": null,
        "PublicAccessBlockConfiguration":
          {
            "BlockPublicAcls": true,
            "BlockPublicPolicy": true,
            "IgnorePublicAcls": true,
            "RestrictPublicBuckets": true,
          },
        "Region": "us-west-2",
        "ResourceId": "arn:aws:s3:::example-bucket",
        "ResourceType": "AWS.S3.Bucket",
        "Tags": { "environment": "pci" },
        "TimeCreated": "2019-01-01T00:00:00.000Z",
        "Versioning": "Enabled",
      }
  - Name: Object Lock Configured With Compliance
    ExpectedResult: true
    Resource:
      {
        "AccountId": "123456789012",
        "Arn": "arn:aws:s3:::example-bucket",
        "EncryptionRules":
          [
            {
              "ApplyServerSideEncryptionByDefault":
                { "KMSMasterKeyID": null, "SSEAlgorithm": "AES256" },
            },
          ],
        "Grants":
          [
            {
              "Grantee":
                {
                  "DisplayName": "example.user",
                  "EmailAddress": null,
                  "ID": "1",
                  "Type": "CanonicalUser",
                  "URI": null,
                },
              "Permission": "FULL_CONTROL",
            },
          ],
        "LifecycleRules": null,
        "LoggingPolicy": null,
        "MFADelete": "Disabled",
        "Name": "example-bucket",
        "ObjectLockConfiguration":
          {
            "ObjectLockEnabled": "Enabled",
            "Rule":
              {
                "DefaultRetention":
                  { "Days": 365, "Mode": "COMPLIANCE", "Years": null },
              },
          },
        "Owner": { "DisplayName": "example.user", "ID": "1" },
        "Policy": null,
        "PublicAccessBlockConfiguration":
          {
            "BlockPublicAcls": true,
            "BlockPublicPolicy": true,
            "IgnorePublicAcls": true,
            "RestrictPublicBuckets": true,
          },
        "Region": "us-west-2",
        "ResourceId": "arn:aws:s3:::example-bucket",
        "ResourceType": "AWS.S3.Bucket",
        "Tags": { "environment": "pci" },
        "TimeCreated": "2019-01-01T00:00:00.000Z",
        "Versioning": "Enabled",
      }
  - Name: Object Lock Not Configured
    ExpectedResult: false
    Resource:
      {
        "AccountId": "123456789012",
        "Arn": "arn:aws:s3:::example-bucket",
        "EncryptionRules":
          [
            {
              "ApplyServerSideEncryptionByDefault":
                { "KMSMasterKeyID": null, "SSEAlgorithm": "AES256" },
            },
          ],
        "Grants":
          [
            {
              "Grantee":
                {
                  "DisplayName": "example.user",
                  "EmailAddress": null,
                  "ID": "1",
                  "Type": "CanonicalUser",
                  "URI": null,
                },
              "Permission": "FULL_CONTROL",
            },
          ],
        "LifecycleRules": null,
        "LoggingPolicy": null,
        "MFADelete": "Disabled",
        "Name": "example-bucket",
        "ObjectLockConfiguration":
          { "ObjectLockEnabled": "Disabled", "Rule": null },
        "Owner": { "DisplayName": "example.user", "ID": "1" },
        "Policy": null,
        "PublicAccessBlockConfiguration":
          {
            "BlockPublicAcls": true,
            "BlockPublicPolicy": true,
            "IgnorePublicAcls": true,
            "RestrictPublicBuckets": true,
          },
        "Region": "us-west-2",
        "ResourceId": "arn:aws:s3:::example-bucket",
        "ResourceType": "AWS.S3.Bucket",
        "Tags": { "environment": "pci" },
        "TimeCreated": "2019-01-01T00:00:00.000Z",
        "Versioning": "Enabled",
      }

Detection logic

Condition

not (not (ObjectLockConfiguration is_null or ObjectLockConfiguration.ObjectLockEnabled ne "Enabled" or ObjectLockConfiguration.Rule is_null) and ObjectLockConfiguration.Rule.DefaultRetention.Mode eq "COMPLIANCE" and ObjectLockConfiguration.Rule.DefaultRetention.Days ge "365")

Exclusions

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

Field	Kind	Excluded values
`ObjectLockConfiguration`	is_null	(no value, null check)
`ObjectLockConfiguration.ObjectLockEnabled`	ne	`Enabled`
`ObjectLockConfiguration.Rule`	is_null	(no value, null check)
`ObjectLockConfiguration.Rule.DefaultRetention.Days`	ge	`365`
`ObjectLockConfiguration.Rule.DefaultRetention.Mode`	eq	`COMPLIANCE`

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
`ObjectLockConfiguration`	is_null	(no value, null check)
`ObjectLockConfiguration.ObjectLockEnabled`	ne	`Enabled`
`ObjectLockConfiguration.Rule`	is_null	(no value, null check)

`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)