Cortex completes OSTIF security audit

Cortex has completed a security audit organized by the Open Source Technology Improvement Fund, with results published through the CNCF Blog. OSTIF credited Quarkslab for the audit work on Cortex, the long-term, multi-tenant scalable open source storage system used with Prometheus and OpenTelemetry.

The audit targeted Cortex as a storage layer that holds metrics and telemetry at scale for multi-tenant environments. In that role it sits behind Prometheus and OpenTelemetry pipelines, so the review focused on the security posture of a system that stores, serves, and isolates long-lived observability data rather than on a single client-side agent or short-lived cache.

For engineers running multi-tenant metrics platforms, an independent audit of Cortex matters because tenant isolation, storage integrity, and exposure of the query and write paths are the surfaces that decide whether a shared Prometheus-compatible backend is safe to operate in production. Builders who already depend on Cortex for long-term retention get an external check on the component that keeps historical series and OpenTelemetry-adjacent workloads.

In the observability market, Cortex competes as the multi-tenant, long-term store option next to other Prometheus-compatible backends. A published OSTIF-backed audit, executed by Quarkslab and surfaced via the CNCF Blog, is a concrete signal for platform teams comparing open source storage choices on security process, not only on scale and query features.

Practical next step: read the full OSTIF audit write-up and Quarkslab findings, map any reported issues to your Cortex deployment topology, and track follow-up patches or configuration guidance from the Cortex maintainers before treating the audit as closed for your environment.