CVE-2026-87913

A missing S3 bucket ownership verification in the AWS Security Agent MCP server before 0.2.0 version might allow remote attackers to obtain the private source archive of a scanned workspace, including credentials and infrastructure state contained in that archive, via a pre-registered storage bucket whose name is derived from a publicly known account identifier. To remediate this issue, users should upgrade to version 0.2.0. Users should also verify that the scan output bucket in their account is owned by their own account, because upgrading does not release a bucket name that a third party has already registered.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-105-aws/
https://github.com/awslabs/mcp/security/advisories/GHSA-3jxw-vj8m-8x77
https://pypi.org/project/awslabs.security-agent-mcp-server/0.2.0/?refid=d8ec3b19-0f37-4f8c-8c12-189f913e205c

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-10 16:18

Updated : 2026-09-10 19:54

NVD link : CVE-2026-87913

Mitre link : CVE-2026-87913

CVE.ORG link : CVE-2026-87913

JSON object : View

Products Affected

No product.

CWE

CWE-283

Unverified Ownership

CWE-341

Predictable from Observable State

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