LoFP LoFP / users testing new model deployments or updated compliance policies without amazon bedrock guardrails.

Techniques

Sample rules

AWS Bedrock Invocations without Guardrails Detected by a Single User Over a Session

Description

Identifies multiple AWS Bedrock executions in a one minute time window without guardrails by the same user in the same account over a session. Multiple consecutive executions implies that a user may be intentionally attempting to bypass security controls, by not routing the requests with the desired guardrail configuration in order to access sensitive information, or possibly exploit a vulnerability in the system.

Detection logic

from logs-aws_bedrock.invocation-*

// Create 1-minute time buckets
| eval Esql.time_window_date_trunc = date_trunc(1 minute, @timestamp)

// Filter for invocations without guardrails
| where gen_ai.guardrail_id is null and user.id is not null

// keep only relevant fields
| keep
  @timestamp,
  Esql.time_window_date_trunc,
  gen_ai.guardrail_id,
  user.id

// count number of unsafe invocations per user
| stats
    Esql.ml_invocations_no_guardrails_count = count()
  by user.id

// Filter for suspicious volume
| where Esql.ml_invocations_no_guardrails_count > 5

// sort descending
| sort Esql.ml_invocations_no_guardrails_count desc