Vulnerability · Published Jun 9, 2026 · Assigned by mongodb
CVE-2026-9747Crafted cross-shard merge aggregation crashes MongoDB Server
Medium 6.5
In plain English
A medium-severity security flaw in MongoDB Server from MongoDB. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities).
Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.3%top 80.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Adding fromRouter:true and runtimeConstants.userRoles could cause aggregations to crash mongodb server.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| MongoDB | MongoDB Server | 8.3.0 – before 8.3.38.2.0 – before 8.2.108.0.0 – before 8.0.247.0.0 – before 7.0.35 |
Weakness: CWE-617 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H