Vulnerability 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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mongodb | Mongodb | >= 7.0.0, < 7.0.40 |
Related Weaknesses (CWE)
References
- https://jira.mongodb.org/browse/SERVER-130264Vendor AdvisoryIssue Tracking
FAQ
What is CVE-2026-18691?
CVE-2026-18691 is a vulnerability with a CVSS score of 8.8 (HIGH). 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...
How severe is CVE-2026-18691?
CVE-2026-18691 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-18691?
Check the references section above for vendor advisories and patch information. Affected products include: Mongodb Mongodb.