CVE-2026-87106

Consul and Consul Enterprise are vulnerable to a denial of service in the native RPC listener that may allow an authenticated client to exhaust server memory before ACL authorization is evaluated. A client that can complete the internal RPC mTLS handshake may exploit this issue without holding a valid ACL token. This vulnerability (CVE-2026-87106) is fixed in Consul 2.0.4 and Consul Enterprise 1.21.18, 1.22.12 and 2.0.4.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://discuss.hashicorp.com/t/hcsec-2026-35-consul-vulnerable-to-a-denial-of-service-in-the-native-rpc-listener/77737

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-10 19:17

Updated : 2026-09-10 19:45

NVD link : CVE-2026-87106

Mitre link : CVE-2026-87106

CVE.ORG link : CVE-2026-87106

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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