CVE-2026-18691 (GCVE-0-2026-18691)
Vulnerability from cvelistv5 – Published: 2026-08-11 18:46 – Updated: 2026-08-11 20:22
VLAI
EPSS
VEX
Title
Improper Authentication in MongoDB Intra-Cluster Connections Allows Credential Exposure
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-11 20:21 UTC
CWE
- CWE-757 - Selection of Less-Secure Algorithm During Negotiation ('Algorithm Downgrade')
Assigner
mongodb
CNA
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| MongoDB | MongoDB Server |
Affected:
8.3.0 , < 8.3.8
(semver)
Affected: 8.0 , < 8.0.29 (semver) Affected: 7.0 , < 7.0.40 (semver) |
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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