CVE-2026-88021

Consul and Consul Enterprise are vulnerable to an authorization bypass in the Connect service mesh that may allow a service to reach a destination it is not authorized to access. When building Envoy RBAC rules to enforce Connect intentions, Consul did not correctly escape certain characters in service names, namespaces, and partitions, causing the generated authorization rules to match more broadly than intended. This vulnerability (CVE-2026-88021) is fixed in Consul 2.0.4 and Consul Enterprise 1.21.18, 1.22.12 and 2.0.4.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://discuss.hashicorp.com/t/hcsec-2026-37-consul-vulnerable-to-an-authorization-bypass-in-the-connect-service-mesh/77739

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-10 19:17

Updated : 2026-09-10 20:17

NVD link : CVE-2026-88021

Mitre link : CVE-2026-88021

CVE.ORG link : CVE-2026-88021

JSON object : View

Products Affected

No product.

CWE

CWE-185

Incorrect Regular Expression

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