CyberSecBulletin
CVE-2026-115413NVD status: Awaiting Analysis

aws-api-mcp-server: Origin Validation Error

CVE-2026-115413 is a high-severity origin validation error vulnerability in aws-api-mcp-server from AWS, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists version 1.6.0 as the first without the flaw, so updating aws-api-mcp-server to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.1% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update aws-api-mcp-server to 1.6.0 or a later version.
  2. Read the advisory on aws.amazon.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
AWSaws-api-mcp-server1.3.0 up to, but not including, 1.6.01.6.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.

Scoring systemScoreSeverityScored by
CVSS 4.07.3HighCNA
CVSS 3.17.8HighCNA

Official description

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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Origin Validation Error

The product does not properly verify that the source of data or communication is valid.

More Origin Validation Error vulnerabilities (CWE-346)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in aws-api-mcp-server

All aws-api-mcp-server vulnerabilities

Recent Origin Validation Error vulnerabilities

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