Description
A flaw in MongoDB's JSON Schema validation error generation code allows an authenticated user with readWrite privileges to crash the mongod server. When a BSON document containing an array with a malformed numeric field name fails a $jsonSchema items type constraint, the error generation path performs unsafe numeric conversion on the user-controlled field name without proper exception handling, resulting in an uncaught exception that terminates the server process. This is possible because incoming wire protocol BSON validation does not enforce that array element field names are valid, in-range numeric indices.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| MongoDB | MongoDB Server | 8.3.0 – < 8.3.9, 8.0.0 – < 8.0.30, 7.0.0 – < 7.0.41 | 8.3.9 |
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-2026-3236 MongoDB Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 8, 2026