---
cve: "CVE-2026-18691"
severity: "CRITICAL"
cvss: 9.0
epss: "23%"
vendor: "MONGODB"
kev: false
exploited: false
published: "2026-08-11 19:17:22"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-09-10T14:12:36+02:00"
---

# CVE-2026-18691

> 9.0 CRITICAL

## Beschreibung

An issue in MongoDB Server's intra-cluster connection setup could allow a party with suitable network access to influence which authentication mechanism is used when one replica set member connects to another. Under certain conditions, this could cause the cluster's shared internal credential to be transmitted in a less-protected form, potentially allowing that credential to be recovered. If recovered, the credential could be used to authenticate as the internal superuser to nodes in the deployment.

## CVSS-Vektor

```
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Benachbart | warn |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Referenzen

- <https://jira.mongodb.org/browse/SERVER-130264>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-18691) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_