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PatchSiren cyber security CVE debrief

CVE-2026-15737 AWS CVE debrief

The AWS Bedrock AgentCore Python SDK, an open-source library for building AI agents on Amazon Bedrock AgentCore, had a vulnerability in versions 1.4.8 and 1.5.0. The OpenTelemetry instrumentation unintentionally logged sensitive user content, including raw user prompts and complete agent responses, without filtering or masking. These logs were written to span attributes and flowed into the customer's aws/spans CloudWatch log group. This exposure could allow a local authenticated user with access to CloudWatch Logs to access sensitive data.

Vendor
AWS
Product
bedrock-agentcore
CVSS
MEDIUM 5.7
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-16
Original CVE updated
2026-07-17
Advisory published
2026-07-16
Advisory updated
2026-07-17

Who should care

Users of AWS Bedrock AgentCore Python SDK versions 1.4.8 and 1.5.0 should be concerned as their sensitive data may have been exposed in CloudWatch Logs. System administrators and security teams responsible for monitoring and managing access to CloudWatch Logs are particularly affected.

Technical summary

The AWS Bedrock AgentCore Python SDK versions 1.4.8 and 1.5.0 had a vulnerability where OpenTelemetry instrumentation logged sensitive user content, including raw user prompts and agent responses, without proper filtering or masking. This sensitive data was written to span attributes and stored in the aws/spans CloudWatch log group, potentially exposing it to local authenticated users with access to these logs.

Defensive priority

Medium priority due to the potential for sensitive data exposure to local authenticated users with access to CloudWatch Logs.

Recommended defensive actions

  • Upgrade to version 1.5.1 or later of the AWS Bedrock AgentCore Python SDK.
  • Review and purge sensitive content from aws/spans CloudWatch log groups for users who ran affected versions.
  • Monitor CloudWatch Logs for sensitive content exposure.
  • Restrict access to CloudWatch Logs to only necessary personnel.
  • Implement additional logging and monitoring to detect potential misuse.

Evidence notes

The CVE record and NVD detail provide information on the vulnerability. The AWS security bulletin and GitHub advisory offer additional context and mitigation strategies. The PyPI page for version 1.5.1 confirms the fix.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-15737 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-15737

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-15737 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-15737

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://aws.amazon.com/security/security-bulletins/2026-058-aws/

    ff89ba41-3aa1-4d27-914a-91399e9639e5

  • Source reference

    Unverified legacy reference

    URL: https://github.com/aws/bedrock-agentcore-sdk-python/security/advisories/GHSA-hqf8-7w95-9r33

    ff89ba41-3aa1-4d27-914a-91399e9639e5

  • Source reference

    Unverified legacy reference

    URL: https://pypi.org/project/bedrock-agentcore/1.5.1/

    ff89ba41-3aa1-4d27-914a-91399e9639e5

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.