CVE-2026-16584: CWE-455 Non-exit on failed initialization in AWS aws-api-mcp-server
Improper handling of an initialization failure in AWS API MCP Server from 0.2.13 through 1.3.46 might allow an actor to bypass the user-configured security policy and execute AWS API operations that the policy was set to deny or gate. When initialization of the security policy enforcement data fails at server startup, the policy check is skipped for the lifetime of the process. IAM permissions on the configured credentials remain in effect and are unaffected. To remediate this issue, users should upgrade to version 1.3.47.
AI Analysis
Technical Summary
CVE-2026-16584 is a vulnerability in the AWS aws-api-mcp-server where failure to properly handle initialization errors of security policy enforcement data causes the server to skip policy checks entirely for the lifetime of the process. This flaw affects versions from 0.2.13 up to and including 1.3.46. Although IAM permissions remain in effect, the bypass of user-configured security policies could allow execution of AWS API operations that would otherwise be denied or gated. AWS has published an advisory and recommends upgrading to version 1.3.47 to remediate the issue.
Potential Impact
The vulnerability allows an attacker to bypass user-configured security policies in the aws-api-mcp-server component, potentially enabling execution of AWS API operations that should be denied. However, IAM permissions on the credentials remain enforced, limiting the scope of unauthorized actions to those permitted by IAM. The overall impact is high due to the potential for unauthorized API operations despite policy restrictions.
Mitigation Recommendations
A patch is available. Users should upgrade aws-api-mcp-server to version 1.3.47 to remediate this vulnerability. Since this is a cloud service, AWS manages remediation for the hosted service; users should verify with the AWS security bulletin for the latest status and ensure their deployments are updated accordingly.
CVE-2026-16584: CWE-455 Non-exit on failed initialization in AWS aws-api-mcp-server
Description
Improper handling of an initialization failure in AWS API MCP Server from 0.2.13 through 1.3.46 might allow an actor to bypass the user-configured security policy and execute AWS API operations that the policy was set to deny or gate. When initialization of the security policy enforcement data fails at server startup, the policy check is skipped for the lifetime of the process. IAM permissions on the configured credentials remain in effect and are unaffected. To remediate this issue, users should upgrade to version 1.3.47.
CVSS v3.1
Score 7.0high
Affected software
pkg:pypi/awslabs-aws-api-mcp-serverRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16584 is a vulnerability in the AWS aws-api-mcp-server where failure to properly handle initialization errors of security policy enforcement data causes the server to skip policy checks entirely for the lifetime of the process. This flaw affects versions from 0.2.13 up to and including 1.3.46. Although IAM permissions remain in effect, the bypass of user-configured security policies could allow execution of AWS API operations that would otherwise be denied or gated. AWS has published an advisory and recommends upgrading to version 1.3.47 to remediate the issue.
Potential Impact
The vulnerability allows an attacker to bypass user-configured security policies in the aws-api-mcp-server component, potentially enabling execution of AWS API operations that should be denied. However, IAM permissions on the credentials remain enforced, limiting the scope of unauthorized actions to those permitted by IAM. The overall impact is high due to the potential for unauthorized API operations despite policy restrictions.
Mitigation Recommendations
A patch is available. Users should upgrade aws-api-mcp-server to version 1.3.47 to remediate this vulnerability. Since this is a cloud service, AWS manages remediation for the hosted service; users should verify with the AWS security bulletin for the latest status and ensure their deployments are updated accordingly.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- AMZN
- Date Reserved
- 2026-07-22T13:43:35.240Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
- Is Cloud Service
- true
- Vendor Advisory Urls
- [{"url":"https://aws.amazon.com/security/security-bulletins/2026-063-aws/","vendor":"AWS"}]
Threat ID: 6a623fe59c2644c7f85af557
Added to database: 07/23/2026, 16:23:01 UTC
Last enriched: 07/23/2026, 16:37:01 UTC
Last updated: 07/23/2026, 23:15:24 UTC
Views: 10
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