CVE-2026-1847: MongoDB

High severity, CVSS 7.5. EPSS: 0.3% chance of exploitation in the next 30 days.

Inserting certain large documents into a replica set could lead to replica set secondaries not being able to fetch the oplog from the primary. This could stall replication inside the replica set leading to server crash.

Affected products

• MongoDB MongoDB: from 7.0.0, before 7.0.29 (fixed in 7.0.29); from 8.0.0, before 8.0.18 (fixed in 8.0.18); from 8.2.0, before 8.2.4 (fixed in 8.2.4)

Published 2026-02-10. Last modified 2026-06-17.