CVE-2026-13055: MongoDB

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

The `$_internalIndexKey` aggregation expression can be used by any authenticated user to crash a MongoDB server (mongod). The expression fails to handle compound wildcard index specifications, triggering an internal consistency check that aborts the server process. The user must be able to run an aggregation pipeline.

Affected products

• MongoDB MongoDB: from 7.0.0, before 7.0.39 (fixed in 7.0.39); from 8.0.0, before 8.0.28 (fixed in 8.0.28); from 8.2.0, before 8.2.12 (fixed in 8.2.12); from 8.3.0, before 8.3.7 (fixed in 8.3.7)

Published 2026-07-22. Last modified 2026-08-05.