What is CVE-2026-18954?

CVE-2026-18954 is a medium-severity vulnerability in Amazon Documentdb Mcp Server, classified under Incorrect Authorization. CVSS score: 5.5/10. Published 2026-08-05.

How severe is CVE-2026-18954?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Auth bypass in Amazon Documentdb Mcp Server

CVE-2026-18954

Incorrect authorization in the aggregation pipeline tool in Amazon AWS Labs DocumentDB MCP Server before 1.0.12 might allow an authenticated MCP client to perform inappropriate write operations on the connected database via write-capable aggregation pipeline stages that bypass the read-only mode enforcement logic. To remediate this issue, users should upgrade to version 1.0.12 or later.

Vulnerability class: Broken Access Control

EPSS: 0.001 (1.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

Affected products

Amazon Documentdb_mcp_server
Aws Documentdb-mcp-server — versions 0

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

ff89ba41-3aa1-4d27-914a-91399e9639e5 (vendor-advisory, Vendor Advisory)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (release-notes, Release Notes, patch)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (release-notes, Vendor Advisory)

Frequently asked questions

What is CVE-2026-18954?: CVE-2026-18954 is a medium-severity vulnerability in Amazon Documentdb Mcp Server, classified under Incorrect Authorization. CVSS score: 5.5/10. Published 2026-08-05.
How severe is CVE-2026-18954?: Medium severity. CVSS v3 base score is 5.5 out of 10.