Maestro: maestro: grpc broker has no auth interceptor and client mtls is optional
Summary
| CVE | CVE-2026-71297 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-05 20:17:25 UTC |
| Updated | 2026-10-05 20:17:25 UTC |
| Description | A flaw was found in the maestro gRPC broker. This vulnerability allows a remote attacker, with a valid client certificate, to bypass authentication. This bypass enables the attacker to subscribe to other consumers' event streams, leading to unauthorized information disclosure, or to publish forged agent status, which can compromise data integrity. |
Risk And Classification
Primary CVSS: v3.1 5.4 MEDIUM from [email protected]
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Problem Types: CWE-306 | CWE-306 Missing Authentication for Critical Function
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 5.4 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
| 3.1 | CNA | CVSS | 5.4 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
LowIntegrity
LowAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Multicluster Engine For Kubernetes | Not specified | Not specified |
| CNA | Red Hat | Multicluster Engine For Kubernetes | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| bugzilla.redhat.com/show_bug.cgi | [email protected] | bugzilla.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-71297 | [email protected] | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-08-05T00:00:00.000Z | Reported to Red Hat. |
| CNA | 2026-10-05T18:00:00.000Z | Made public. |
Workarounds
CNA: To mitigate this issue, ensure that client mTLS is enabled for the Maestro gRPC broker by configuring the `BrokerClientCAFile` parameter. If the gRPC message broker type is not required, avoid enabling it. If the gRPC broker is in use, a restart or service reload may be required after applying the configuration changes.
There are currently no legacy QID mappings associated with this CVE.