---
id: CVE-2026-18697
title: >-
  An issue in MongoDB Server's aggregation framework could allow an
  unauthenticated party to cause a mongos (router) process to terminate
  unexpectedly by submitting a specially formed aggregation command
summary: >-
  An issue in MongoDB Server's aggregation framework could allow an
  unauthenticated party to cause a mongos (router) process to terminate
  unexpectedly by submitting a specially formed aggregation command. This could
  result in a denial of s…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-617
vendor: mongodb
product: mongodb
affected:
  - 'mongodb >= 7.0.0, < 7.0.40'
  - 'mongodb >= 8.0.0, < 8.0.29'
  - 'mongodb >= 8.2.0, <= 8.2.12'
  - 'mongodb >= 8.3.0, < 8.3.8'
  - mongodb = 9.0.0
  - mongodb = 9.1.0
patched:
  - mongodb 8.3.8
published: '2026-08-11'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T15:17:42.620'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-18697'
references:
  - url: 'https://jira.mongodb.org/browse/SERVER-130110'
    label: cna@mongodb.com
tags:
  - nvd
epss: 0.00331
epssPercentile: 0.26441
ingestedAt: '2026-08-29T19:41:15.761Z'
---

## Overview

An issue in MongoDB Server's aggregation framework could allow an unauthenticated party to cause a mongos (router) process to terminate unexpectedly by submitting a specially formed aggregation command. This could result in a denial of service, disrupting client connections routed through the affected mongos instance.

## Affected

- `mongodb >= 7.0.0, < 7.0.40`
- `mongodb >= 8.0.0, < 8.0.29`
- `mongodb >= 8.2.0, <= 8.2.12`
- `mongodb >= 8.3.0, < 8.3.8`
- `mongodb = 9.0.0`
- `mongodb = 9.1.0`

## Remediation

Upgrade past the affected range:

- `mongodb 8.3.8`