Quarterly Release: October 2026¶

Current Versions¶

Upgrading to October Release¶

Follow the upgrade guide for details on how to successfully upgrade to the October release.

Initial Release: October 30, 2026¶

Backend Updates¶

Features¶

• Prefect 3.8 Client Support — The server is now tested against Prefect 3.8.8 clients.
• Filter Automations by ID — The automations filter accepts an id criterion, and POST /automations/count accepts the same filter so counts match filtered reads. Prefect 3.8.5+ clients send this field, so looking up automations by name (for example prefect automation inspect <name>) previously failed with a 422.
• Cancel Paused Flow Runs — Paused flow runs can now be moved to Cancelling, including blocking pauses whose pause timeout has already passed. Previously these cancellations were rejected or turned into Failed.

Bug Fixes¶

• Deployment Concurrency Leases Across Retries — A flow run that retries in-process now keeps its deployment concurrency lease through AwaitingRetry, instead of the lease being revoked and the run cancelled mid-retry.
• Renewed Concurrency Leases No Longer Reaped — The concurrency lease reaper re-checks a lease's expiration before revoking it, so a lease renewed after the expiry scan is left in place.
• Zero-Limit Pagination — limit=0 on the flow, flow run, task run, deployment, deployment version, and worker /paginate endpoints now returns zero pages instead of a 500.
• Literal Event Text Search — _ and % in event text searches now match literally rather than as wildcards.
• Oversized Event Logging — The warning logged when an oversized event is refused now includes the event's size.

Maintenance¶

• Dependency Updates — Python dependencies have been updated to current major versions, including griffe, kubernetes-asyncio, markupsafe, requests-oauthlib, tzdata, and watchfiles.
• Security Updates — Updated dnspython to 2.9.0 for CVE-2026-114605.

Frontend Updates¶

Bug Fixes¶

• Deployment Runs Refresh — The Runs and Upcoming tabs on a deployment page now refresh every 30 seconds, so new runs and state changes appear without reloading the page.
• Audit Log Workspaces — The account audit log now shows the workspace for workspace-level events even when the event does not list the workspace among its related resources. The workspace filter lists every workspace in the account rather than only those that appear in loaded events.

Maintenance¶

• Security Updates — Updated frontend dependencies, including axios, dompurify, vue, katex, and mermaid, and moved the Node.js version used to build the UI to 22.23.4.

Helm Chart Updates¶

• Prefect Istio Chart 1.4.0 — Bundles Istio 1.31.3, up from 1.30.3. The bundled Istio gateway is updated to match. Upgrade notes:
  • Images — All Istio images come from docker.io/istio at tag 1.31.3 (pilot, proxyv2, and install-cni when CNI is enabled). If you enabled Istio CNI on the July release, install-cni was pulled from registry.istio.io/release; mirror it from docker.io/istio instead.
  • Istio defaults — Istio 1.31's default behavior changes are taken as is. None of them affect the configuration that Prefect's charts install.
  • Security fixes — Includes fixes for an AuthorizationPolicy method-rule bypass over HTTP/2 (GHSA-w44g-8m76-8gc5), BackendTLSPolicy plaintext fallback on sidecars (GHSA-qm8v-g4f9-qhjx), and Envoy CVEs.
• Traefik Auth Proxy Image — The default Traefik auth proxy image tag has been updated from 3.7.8 to 3.7.16.