# CVE-2026-104005: Incorrect authorization in MongoDB Server router for bulk writes to system namespaces

> An authenticated user with readWrite privileges can crash the MongoDB mongos router via a crafted aggregation pipeline, causing denial of service.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Oct 2026
- **Updated:** 15 Oct 2026
- **Also known as:** GHSA-56w2-wpqh-pq52, UBUNTU-CVE-2026-104005

## What is CVE-2026-104005?

CVE-2026-104005 is a high-severity missing authorization vulnerability in MongoDB Server, published on 13 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A security issue was discovered in MongoDB mongos (the sharded cluster router) where an authenticated user with readWrite privileges could crash the mongos process by crafting a specially formed aggregation pipeline. The issue leverages an internal aggregation stage that lacks proper authorization checks despite being intended for internal use, allowing a subsequent stage to be forced to execute on the router under conditions it was not designed to handle. This results in an unhandled fatal error that causes the mongos process to immediately abort, resulting in denial of service for all clients routed through the affected mongos instance.

Weakness: CWE-617 (Reachable Assertion)

## Which versions are affected by CVE-2026-104005?


## How do I fix CVE-2026-104005?

No fix has been published for CVE-2026-104005 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-104005 being exploited?

There is no known exploitation of CVE-2026-104005 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-104005 and fix it if it is affected.

What it is: CVE-2026-104005 is a high-severity missing authorization vulnerability in MongoDB Server, published on 13 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-104005 in the wild and no public exploit code.

Affected product: MongoDB 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-2026-104005/ (Markdown: https://insights.sbomify.com/CVE-2026-104005/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-104005
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-104005
- OSV: https://osv.dev/vulnerability/CVE-2026-104005

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-104005/
Summaries are generated and may contain mistakes; the official description above is the record.