# CVE-2026-18954: Incorrect authorization in the aggregation pipeline tool in Amazon AWS Labs DocumentDB MCP Server

> Authenticated clients can bypass read-only restrictions to perform unauthorized write operations on the database via aggregation pipelines.

- **Severity:** Medium 5.7 (`CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 5 Aug 2026
- **Updated:** 6 Aug 2026
- **Also known as:** GHSA-j694-4m5j-w8hc, GHSA-w95p-h69m-853r

## What is CVE-2026-18954?

CVE-2026-18954 is a medium-severity missing authorization vulnerability in AWS documentdb-mcp-server, published on 5 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-18954?

It affects 1 product.


Products: Amazon Documentdb Mcp Server.

## How do I fix CVE-2026-18954?

No fix has been published for CVE-2026-18954 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-18954 being exploited?

There is no known exploitation of CVE-2026-18954 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-18954 and fix it if it is affected.

What it is: CVE-2026-18954 is a medium-severity missing authorization vulnerability in AWS documentdb-mcp-server, published on 5 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-18954 in the wild and no public exploit code.

Affected product: AWS documentdb-mcp-server. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-18954/ (Markdown: https://insights.sbomify.com/CVE-2026-18954/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-18954
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-18954
- OSV: https://osv.dev/vulnerability/CVE-2026-18954

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-18954/
Summaries are generated and may contain mistakes; the official description above is the record.