Description
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
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| MongoDB | MongoDB Server | 7.0 – < 7.0.39, 8.0 – < 8.0.28, 8.2.0 – < 8.2.12, 8.3.0 – < 8.3.7 | 7.0.39 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | mongodb | No fix yet | — |
| Ubuntu Pro 18.04 LTS | mongodb | No fix yet | — |
| Ubuntu Pro 16.04 LTS | mongodb | No fix yet | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | mongodb | No fix yet | — |
Advisories 1
- WID-SEC-2026-2487 MongoDB: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jul 22, 2026