---
title: AWS Bedrock Unauthorized Resource-Based Policy Modification Attempt
description: Detects failed, access-denied attempts to modify or delete resource-based access policies on AWS Bedrock resources via the PutResourcePolicy and DeleteResourcePolicy...
url: https://www.elastic.co/docs/reference/security/prebuilt-rules/rules/integrations/aws/persistence_bedrock_resource_based_policy_denied_attempt
products:
  - Elastic Security
---

# AWS Bedrock Unauthorized Resource-Based Policy Modification Attempt
Detects failed, access-denied attempts to modify or delete resource-based access policies on AWS Bedrock resources via
the PutResourcePolicy and DeleteResourcePolicy API calls. Resource-based policies govern which principals (including
external accounts) may access Bedrock resources such as agents, knowledge bases, and custom models. A principal that is
repeatedly denied when attempting to attach or remove these policies may be a compromised or under-privileged identity
probing for the ability to grant external or cross-account access, or to weaken existing access controls. Unlike the
companion rule that detects successful changes, this rule surfaces the attempt itself, which is a high-signal indicator
of credential boundary-testing even though no change occurred.
**Rule type**: query
**Rule indices**:
- logs-aws.cloudtrail-*

**Rule Severity**: low
**Risk Score**: 21
**Runs every**: 
**Searches indices from**: `now-6m`
**Maximum alerts per execution**: 100
**References**:
- [[https://docs.aws.amazon.com/bedrock/latest/APIReference/API_PutResourcePolicy.html](https://docs.aws.amazon.com/bedrock/latest/APIReference/API_PutResourcePolicy.html)](https://docs.aws.amazon.com/bedrock/latest/APIReference/API_PutResourcePolicy.html)
- [[https://docs.aws.amazon.com/bedrock/latest/APIReference/API_DeleteResourcePolicy.html](https://docs.aws.amazon.com/bedrock/latest/APIReference/API_DeleteResourcePolicy.html)](https://docs.aws.amazon.com/bedrock/latest/APIReference/API_DeleteResourcePolicy.html)

**Tags**:
- Domain: Cloud
- Domain: GenAI
- Data Source: AWS
- Data Source: AWS CloudTrail
- Data Source: Amazon Web Services
- Data Source: AWS Bedrock
- Data Source: Amazon Bedrock
- Use Case: Identity and Access Audit
- Resources: Investigation Guide
- Tactic: Persistence
- Noise: Unknown
- Performance: Fast
- Threat: Unauthorized AI Usage
- Rule Type: Custom Query (KQL)
- Platform: AWS
- Service: AWS Bedrock
- Mitre Atlas: AML.T0012

**Version**: 2
**Rule authors**:
- Elastic

**Rule license**: Elastic License v2

## Investigation guide


## Triage and analysis


### Investigating AWS Bedrock Unauthorized Resource-Based Policy Modification Attempt

AWS Bedrock resource-based policies control which principals can access Bedrock resources such as agents,
knowledge bases, and custom models. An adversary who has compromised a credential may attempt to attach a policy
that grants an external principal access for persistence or cross-account access, or delete a policy to break
existing access controls. This rule detects `PutResourcePolicy` and `DeleteResourcePolicy` calls that were denied
(`AccessDenied` / unauthorized), which indicates an identity attempting an action it is not permitted to perform —
a strong signal of boundary-testing by a compromised or under-privileged principal even though the change did not
take effect.

#### Possible investigation steps

- **Identify the actor and context**
  - Review `aws.cloudtrail.user_identity.arn`, `aws.cloudtrail.user_identity.type`,
    `aws.cloudtrail.user_identity.access_key_id`, `user_agent.original`, and `source.ip`.
  - Determine whether this identity has any legitimate reason to manage Bedrock resource policies. A denial for an
    identity that should never touch these APIs is more suspicious than one from an admin with a transient gap.
- **Assess the attempt**
  - Inspect `aws.cloudtrail.error_code` and `aws.cloudtrail.error_message` to confirm the denial reason.
  - For `PutResourcePolicy`, review `aws.cloudtrail.request_parameters` and
    `aws.cloudtrail.flattened.request_parameters` for the target resource ARN and the attempted policy document.
    Look for `Principal` values referencing external AWS account IDs, `"*"`, or unfamiliar roles.
- **Correlate activity**
  - Look for repeated denials across Bedrock or IAM APIs from the same identity, which can indicate permission
    enumeration or escalation attempts.
  - Check whether the identity later succeeded (e.g., after acquiring new permissions) on the same or related
    resources, and review any IAM changes in the surrounding window.


### False positive analysis

- **Permission gaps**: Newly provisioned roles/users or IaC pipelines running before policy grants are applied may
  generate transient denials. Validate against change tickets and known automation.
- **Exploration in non-production**: Developers testing in sandbox accounts may hit denials. Confirm the account and
  identity context.


### Response and remediation

- If the attempt is unexpected, treat the identity as potentially compromised: disable or rotate the credentials in
  `aws.cloudtrail.user_identity.access_key_id` and review the actor's recent activity.
- Review all Bedrock and IAM activity from the same identity in the surrounding time window for successful access
  grants, permission changes, or other persistence attempts.
- Confirm least-privilege on `bedrock:PutResourcePolicy` and `bedrock:DeleteResourcePolicy`, and alert on both denied
  and successful calls.


## Rule Query

```kuery
data_stream.dataset: "aws.cloudtrail" and
    event.provider: "bedrock.amazonaws.com" and
    event.action: ("PutResourcePolicy" or "DeleteResourcePolicy") and
    event.outcome: "failure" and
    aws.cloudtrail.error_code: (
        "AccessDenied" or
        "AccessDeniedException"
    )
```

**Framework:** MITRE ATT&CK
- Tactic:
  - Name: Persistence
  - Id: TA0003
  - Reference URL: [[https://attack.mitre.org/tactics/TA0003/](https://attack.mitre.org/tactics/TA0003/)](https://attack.mitre.org/tactics/TA0003/)
- Technique:
  - Name: Account Manipulation
  - Id: T1098
  - Reference URL: [[https://attack.mitre.org/techniques/T1098/](https://attack.mitre.org/techniques/T1098/)](https://attack.mitre.org/techniques/T1098/)