CVE-2026-18697 Improper Input Validation in MongoDB Aggregation Framework Allows Unauthenticated Denial of Service on mongos
Unauthenticated attackers can crash the mongos router process via a specially crafted aggregation command, causing service disruption.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-18697?
CVE-2026-18697 is a high-severity denial of service vulnerability in Mongodb Mongodb, published on 11 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-617
Which versions are affected by CVE-2026-18697?
1 open source package ship an affected version, including mongodb. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mongodb Bitnami | From 7.0.0 | 7.0.40, 8.0.29, 8.3.8, 9.0.2 |
Products include Mongodb Mongodb.
How do I fix CVE-2026-18697?
Upgrade mongodb to a fixed version for your release line: 7.0.40, 8.0.29, 8.3.8 or 9.0.2.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-18697 being exploited?
There is no known exploitation of CVE-2026-18697 in the wild and no public exploit code.
Other vulnerabilities in Mongodb Mongodb
- CVE-2025-14847 MongoDB and MongoDB Server Improper Handling of Length Parameter Inconsistency
- CVE-2026-82067 Auth bypass in MongoDB Server
- CVE-2026-13072 MongoDB Improper Input Validation in Compute Mode External Data Processing Leading to Memory Corruption
- CVE-2017-15535 Denial of service in n/a
- CVE-2026-18691 Improper Authentication in MongoDB Intra-Cluster Connections Allows Credential Exposure
Sources
Also known as BIT-mongodb-2026-18697, GHSA-wxp5-7rcf-9m3q, MINI-95w6-w8c3-xfqp, MINI-fhq4-fr9v-2x9j, MINI-qmgw-g57v-xc29, MINI-xprx-cfjc-2j9h and 1 more.