Vulnerability · Published Sep 10, 2026 · Assigned by AMZN
CVE-2026-87913Missing S3 bucket ownership verification in the AWS Security Agent MCP server
Medium 5.9
In plain English
A medium-severity security flaw in AWS Security Agent MCP server from AWS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 39% of all known vulnerabilities).
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| AWS | AWS Security Agent MCP server | 0.1.0 – through 0.1.5 |
Weakness: CWE-283, CWE-341 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:L/A:N