# CVE-2026-9747: Crafted cross-shard merge aggregation crashes MongoDB Server

CVE-2026-9747 is fixed in MongoDB on 1 platform by MongoDB 8.3.3 (version 8.3.3), released May 28, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-9747
- Priority: High
- CVSS: 7.1
- EPSS: 0.0027
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 9, 2026
- Weakness: CWE-617: Reachable assertion
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-9747

## Description

Adding fromRouter:true and runtimeConstants.userRoles could cause aggregations to crash mongodb server.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | MongoDB | 8.3.3 | [MongoDB 8.3.3](https://patchblox.com/security/data/fix/windows-app/mongodb.server-8.3.3.md) | May 28, 2026 |

---

Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.