CVE-2026-82059: MongoDB

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

An internal aggregation expression in MongoDB Server was incorrectly registered as accessible to any authenticated user rather than being restricted to internal cluster operations. By crafting a malformed index specification within this expression, an authenticated user with read-only privileges could trigger an assertion failure in the index key generation code path. In certain build configurations, this assertion failure results in termination of the mongod process, causing a denial of service to all connected clients.

Affected products

• MongoDB MongoDB: from 7.0.0, before 7.0.41 (fixed in 7.0.41); from 8.0.0, before 8.0.30 (fixed in 8.0.30); from 8.3.0, before 8.3.9 (fixed in 8.3.9)

Published 2026-09-08. Last modified 2026-09-16.