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TI-2026-81501 Aliases CVE-2026-115413

Missing token audience validation in AWS API MCP Server OAuth mode

Priority LOW 33CWE-346Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-346.

Summary

AWS API MCP Server before 1.6.0 does not validate the audience of OAuth access tokens when OAuth authentication mode is enabled, so it accepts tokens issued to other applications by the same identity provider. A local user who holds such a token can run AWS operations with the server's configured AWS credentials, which relates to CWE-346.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

Missing token audience validation in the OAuth authentication mode of AWS API MCP Server before version 1.6.0 might allow local users to run AWS operations with the server's configured AWS credentials via an access token issued to another application by the same identity provider. To remediate this issue, users should upgrade to version 1.6.0 and configure the expected token audience or client ID for the server.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00097 0th percentileScored 2026-11-07
Fix Fixed aws-api-mcp-server (AWS): 1.6.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
AWSaws-api-mcp-server1.3.0 to before 1.6.01.6.0Patch availableCNA
  • aws-api-mcp-server VendorAWS Affected 1.3.0 to before 1.6.0 Fixed in 1.6.0 Patch available CNA

Remediation

Upgrade aws-api-mcp-server to version 1.6.0. Configure the expected token audience or client ID for the server.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

  • Fix · CNA aws-api-mcp-server (AWS) Fixed in 1.6.0

Timeline

  1. 2026-10-27 Threatist record created from CVE-2026-115413
  2. 2026-10-28 Priority changed: MEDIUM → LOW
  3. 2026-11-04 CISA SSVC decision points changed

References

Patch 1

Advisory 2

  • TI-2026-23989 crypto: algif_aead - Revert to operating out-of-place KEVCVSS 3.1HIGH 7.8
  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2024-18648 Amazon AWS Amplify CLI before 12.10.1 incorrectly configures the role trust policy of IAM… CVSS 3.1CRITICAL 9.8
  • TI-2024-05929 Openssh: regresshion - race condition in ssh allows rce/dos CVSS 3.1HIGH 8.1
  • TI-2025-03847 Input validation issue in AWS Amplify Studio UI component properties CVSS 4.0CRITICAL 9.0
  • TI-2026-11603 HTTP/2 Stream Parser Confusion Body-Inspection Bypass in Amazon CloudFront with AWS WAF CVSS 4.0HIGH 7.9
See all 383 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences