CVE-2026-18691
Last modified
CVE-2026-18691 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. 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. EPSS estimates a 0.24% chance of exploitation in the next 30 days.
Description
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.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Mongodb | Mongodb | >= 7.0.0, < 7.0.40 | — |
| Mongodb | Mongodb | >= 8.0.0, < 8.0.29 | — |
| Mongodb | Mongodb | >= 8.2.0, <= 8.2.12 | — |
| Mongodb | Mongodb | >= 8.3.0, < 8.3.8 | — |
| Mongodb | Mongodb | 9.0.0 | Alpha0 |
| Mongodb | Mongodb | 9.1.0 | Alpha0 |
References
- https://jira.mongodb.org/browse/SERVER-130264Vendor Advisory, Issue Tracking
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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