CVE-2026-18711: MongoDB

High severity, CVSS 7.1. EPSS: 0.5% chance of exploitation in the next 30 days.

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.

Affected products

• MongoDB MongoDB: from 7.0.0, up to and including 7.0.40; from 8.0.0, before 8.0.29 (fixed in 8.0.29); from 8.2.0, up to and including 8.2.12; from 8.3.0, before 8.3.8 (fixed in 8.3.8); version 9.0.0 only; version 9.1.0 only

Published 2026-08-11. Last modified 2026-09-25.