CVE-2026-81664

The OpenFaaS gateway registers GET /system/telemetry in gateway/main.go and, when basic_auth is enabled, wraps each administrative /system/* handler in auth.DecorateWithBasicAuth. TelemetryHandler was left out of that wrap block from 0.27.11, which introduced the route, until 0.27.14, which added it. On an affected gateway the route therefore reaches the forwarding proxy with no credential check and returns whatever the configured provider serves for /system/telemetry, so any client that can reach the gateway port can read the provider's telemetry regardless of the basic_auth setting. The exposed content depends on the provider, and covers resource and invocation metrics for faasd and pod or cluster state for faas-netes.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/geo-chen/oss/blob/main/faas.md
https://github.com/openfaas/faas
https://github.com/openfaas/faas/blob/0.27.13/gateway/main.go#L216
https://github.com/openfaas/faas/commit/8d803bf9e2655aec6a60fd0e25b392839f96af95
https://www.vulncheck.com/advisories/openfaas-gateway-0.27.11-through-0.27.13-missing-authentication-on-the-system-telemetry-route
https://github.com/geo-chen/oss/blob/main/faas.md

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-27 17:20

Updated : 2026-08-31 16:19

NVD link : CVE-2026-81664

Mitre link : CVE-2026-81664

CVE.ORG link : CVE-2026-81664

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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