AWS Bedrock Guardrail Updated or Deleted

Severity: medium
Log types: AWS.CloudTrail
Tags: AWS, Bedrock, Generative AI Guardrails, AML.T0054, LLM Jailbreak, Impair Defenses: Disable or Modify Tools, Defense Evasion
Reference: https://docs.aws.amazon.com/bedrock/latest/APIReference/API_DeleteGuardrail.html
Source: github.com/panther-labs/panther-analysis

An Amazon Bedrock Guardrail was updated or deleted. Amazon Bedrock Guardrails are used to implement application-specific safeguards based on your use cases and responsible AI policies. Updating or deleting a guardrail can have security implications to your AI workloads.

MITRE ATT&CK coverage

Tactic	Techniques
Stealth	`T1562.001` Impair Defenses: Disable or Modify Tools

Rules detecting the same action

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

AWS Bedrock Delete GuardRails (Splunk)
AWS Bedrock Guardrail Deleted or Weakened (Elastic)

Rule body yaml

AnalysisType: rule
Filename: aws_bedrock_guardrail_update_delete.py
RuleID: "AWS.Bedrock.GuardrailUpdateDelete"
DisplayName: "AWS Bedrock Guardrail Updated or Deleted"
Enabled: true
LogTypes:
  - AWS.CloudTrail
Tags:
  - AWS
  - Bedrock
  - Generative AI Guardrails
  - AML.T0054
  - LLM Jailbreak
  - "Impair Defenses: Disable or Modify Tools"
  - Defense Evasion
Severity: Medium
Reports:
  MITRE ATT&CK:
    - TA0005:T1562.001 # Impair Defenses: Disable or Modify Tools
Description: >
  An Amazon Bedrock Guardrail was updated or deleted.
  Amazon Bedrock Guardrails are used to implement application-specific safeguards based on your use cases and responsible AI policies.
  Updating or deleting a guardrail can have security implications to your AI workloads.
Runbook: |
  Review the guardrail update or deletion to ensure that it was authorized and that it does not introduce security risks to your AI workloads.
  If the guardrail update or deletion was unauthorized, investigate the incident and take appropriate action.
  https://atlas.mitre.org/mitigations/AML.M0020
Reference: https://docs.aws.amazon.com/bedrock/latest/APIReference/API_DeleteGuardrail.html
SummaryAttributes:
  - userAgent
  - sourceIpAddress
  - recipientAccountId
  - p_any_aws_arns
Tests:
  - Name: Guardrail Updated
    ExpectedResult: true
    Log:
      {
        "awsRegion": "us-west-2",
        "eventCategory": "Management",
        "eventID": "4d482238-d0c5-4337-800f-d1ed79957fd4",
        "eventName": "UpdateGuardrail",
        "eventSource": "bedrock.amazonaws.com",
        "eventTime": "2025-01-21 17:39:10.000000000",
        "eventType": "AwsApiCall",
        "eventVersion": "1.09",
        "managementEvent": true,
        "readOnly": false,
        "recipientAccountId": "123123123123",
        "requestID": "4ebcfaab-52e6-4027-9307-dbfe671b1cdb",
        "requestParameters": {
          "guardrailIdentifier": "cmy5azq5koeo",
          "name": "HIDDEN_DUE_TO_SECURITY_REASONS"
        },
        "responseElements": {
          "guardrailArn": "arn:aws:bedrock:us-west-2:123123123123:guardrail/cmy5azq5koeo",
          "guardrailId": "cmy5azq5koeo",
          "updatedAt": "2025-01-21T17:39:10.379877250Z",
          "version": "DRAFT"
        },
        "sessionCredentialFromConsole": true,
        "sourceIPAddress": "123.123.123.123",
        "tlsDetails": {
          "cipherSuite": "TLS_AES_128_GCM_SHA256",
          "clientProvidedHostHeader": "bedrock.us-west-2.amazonaws.com",
          "tlsVersion": "TLSv1.3"
        },
        "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
        "userIdentity": {
          "accessKeyId": "ASIAQWERQWERQWERQWER",
          "accountId": "123123123123",
          "arn": "arn:aws:sts::123123123123:assumed-role/DevAdmin/dr.evil",
          "principalId": "AROAQWERQWERQWERQWER:dr.evil",
          "sessionContext": {
            "attributes": {
              "creationDate": "2025-01-21T16:08:03Z",
              "mfaAuthenticated": "false"
            },
            "sessionIssuer": {
              "accountId": "123123123123",
              "arn": "arn:aws:iam::123123123123:role/aws-reserved/sso.amazonaws.com/us-west-2/DevAdmin",
              "principalId": "AROAQWERQWERQWERQWER",
              "type": "Role",
              "userName": "DevAdmin"
            }
          },
          "type": "AssumedRole"
        }
      }
  - Name: Guardrail Deleted
    ExpectedResult: true
    Log: 
      {
        "awsRegion": "us-west-2",
        "eventCategory": "Management",
        "eventID": "3105145b-d0ca-41ab-a0fd-73f4f31ccbd1",
        "eventName": "DeleteGuardrail",
        "eventSource": "bedrock.amazonaws.com",
        "eventTime": "2025-01-21 18:12:33.000000000",
        "eventType": "AwsApiCall",
        "eventVersion": "1.09",
        "managementEvent": true,
        "readOnly": false,
        "recipientAccountId": "123123123123",
        "requestID": "6e6cadb2-ad15-4c46-9900-fd1888e01ee1",
        "requestParameters": {
          "guardrailIdentifier": "cmy5azq5koeo"
        },
        "sessionCredentialFromConsole": true,
        "sourceIPAddress": "123.123.123.123",
        "tlsDetails": {
          "cipherSuite": "TLS_AES_128_GCM_SHA256",
          "clientProvidedHostHeader": "bedrock.us-west-2.amazonaws.com",
          "tlsVersion": "TLSv1.3"
        },
        "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
        "userIdentity": {
          "accessKeyId": "ASIAQWERQWERQWERQWER",
          "accountId": "123123123123",
          "arn": "arn:aws:sts::123123123123:assumed-role/DevAdmin/dr.evil",
          "principalId": "AROAQWERQWERQWERQWER:dr.evil",
          "sessionContext": {
            "attributes": {
              "creationDate": "2025-01-21T16:08:03Z",
              "mfaAuthenticated": "false"
            },
            "sessionIssuer": {
              "accountId": "123123123123",
              "arn": "arn:aws:iam::123123123123:role/aws-reserved/sso.amazonaws.com/us-west-2/DevAdmin",
              "principalId": "AROAQWERQWERQWERQWER",
              "type": "Role",
              "userName": "DevAdmin"
            }
          },
          "type": "AssumedRole"
        }
      }
  - Name: List Guardrails
    ExpectedResult: false
    Log: 
      {
        "awsRegion": "us-west-2",
        "eventCategory": "Management",
        "eventID": "906c4056-df1e-4565-a40b-2ba216a0c849",
        "eventName": "ListGuardrails",
        "eventSource": "bedrock.amazonaws.com",
        "eventTime": "2025-01-21 18:12:33.000000000",
        "eventType": "AwsApiCall",
        "eventVersion": "1.09",
        "managementEvent": true,
        "readOnly": true,
        "recipientAccountId": "123123123123",
        "requestID": "9219ab18-cddf-4376-afc6-cc4edf2c2f0f",
        "requestParameters": {
          "maxResults": 1000
        },
        "sessionCredentialFromConsole": true,
        "sourceIPAddress": "123.123.123.123",
        "tlsDetails": {
          "cipherSuite": "TLS_AES_128_GCM_SHA256",
          "clientProvidedHostHeader": "bedrock.us-west-2.amazonaws.com",
          "tlsVersion": "TLSv1.3"
        },
        "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
        "userIdentity": {
          "accessKeyId": "ASIAQWERQWERQWERQWER",
          "accountId": "123123123123",
          "arn": "arn:aws:sts::123123123123:assumed-role/DevAdmin/dr.evil",
          "principalId": "AROAQWERQWERQWERQWER:dr.evil",
          "sessionContext": {
            "attributes": {
              "creationDate": "2025-01-21T16:08:03Z",
              "mfaAuthenticated": "false"
            },
            "sessionIssuer": {
              "accountId": "123123123123",
              "arn": "arn:aws:iam::123123123123:role/aws-reserved/sso.amazonaws.com/us-west-2/DevAdmin",
              "principalId": "AROAQWERQWERQWERQWER",
              "type": "Role",
              "userName": "DevAdmin"
            }
          },
          "type": "AssumedRole"
        }
      }

Detection logic

Condition

eventSource eq "bedrock.amazonaws.com"
eventName in ["DeleteGuardrail", "UpdateGuardrail"]
not (errorCode is_not_null or errorMessage is_not_null)

Exclusions

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

Field	Kind	Excluded values
`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	`DeleteGuardrail` `UpdateGuardrail`
`eventSource`	eq	`bedrock.amazonaws.com`

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	Source
`eventName`
`eventSource`
`awsRegion`
`recipientAccountId`
`sourceIPAddress`
`userAgent`
`userIdentity`
`actor_user`
`guardrailIdentifier`	`requestParameters.guardrailIdentifier`

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`/`	Focus search
`?`	Toggle this help
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`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)