CVE-2026-16584 (GCVE-0-2026-16584)
Vulnerability from cvelistv5 – Published: 2026-07-23 15:34 – Updated: 2026-07-23 18:16
VLAI
EPSS
VEX
Title
AWS API MCP Server Security Policy Bypass via Startup Failure
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
- CWE-455 - Non-exit on failed initialization
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://pypi.org/project/awslabs.aws-api-mcp-serv… | release-notespatch |
| https://aws.amazon.com/security/security-bulletin… | vendor-advisory |
| https://github.com/awslabs/mcp/security/advisorie… | release-notes |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| AWS | aws-api-mcp-server |
Affected:
0.2.13 , < 1.3.47
(custom)
|
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
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