CVE-2026-81664
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. Limited direct impact.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 6.9 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-306 · Missing authentication
- Record status
- Deferred
Attack profile CVSS 4.0 · 6.9
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- None
- Privileges needed
- None
- User interaction
- None
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-81664.md and follow it. Check whether this project is affected by CVE-2026-81664. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
References
- 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