CVE-2026-18711 Use-After-Free in MongoDB Query Execution Engine Leads to Denial of Service and Potential Memory Disclosure
Authenticated users can trigger a use-after-free in MongoDB's query engine, causing server crashes or memory disclosure via time-series collections.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-18711?
CVE-2026-18711 is a high-severity use after free vulnerability in Mongodb Mongodb, published on 11 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
An issue in MongoDB Server's query execution engine could allow an authenticated user with read and write privileges to cause an internal reference to be used after the underlying memory has been freed, when running certain queries against time-series collections. This could result in a server crash or disclosure of freed memory contents within query results.
Weakness: CWE-416
Which versions are affected by CVE-2026-18711?
1 open source package ship an affected version, including mongodb. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mongodb Bitnami | From 7.0.0 | 7.0.41, 8.0.29, 8.3.8, 9.0.2 |
Products include Mongodb Mongodb.
How do I fix CVE-2026-18711?
Upgrade mongodb to a fixed version for your release line: 7.0.41, 8.0.29, 8.3.8 or 9.0.2.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-18711 being exploited?
There is no known exploitation of CVE-2026-18711 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-2026-18711, GHSA-xv7q-6jr5-mw96, MINI-2v7h-9fhh-pmv9, MINI-6rhf-rhmq-v8h5, MINI-7gf3-2rxf-c47q, MINI-v5gv-4x6h-hc7v and 1 more.