---
id: "CVE-2026-104615"
kind: "vulnerability"
aliases: ["CVE-2026-104615"]
title: "Rancher Fleet: cluster registration accepts identity not bound to its token"
severity: "high"
cvss: 7.9
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["fleet", "infrastructure", "kubernetes", "rancher", "self-hosted"]
not_affected_if: ["fleet-not-used", "version-outside-range"]
published_at: "2026-10-30T16:17:36+00:00"
first_seen_at: "2026-10-30T16:31:25+00:00"
updated_at: "2026-10-30T16:31:59+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-104615", "first_seen_at": "2026-10-30T16:31:25+00:00"}]
---

# Rancher Fleet: cluster registration accepts identity not bound to its token

Fleet, the Rancher tool that manages groups of Kubernetes clusters, accepted a cluster identity in a registration request without checking it against the registration token used. An attacker can associate a registration with a managed cluster that was originally registered with a different token.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the Fleet version deployed in the management cluster, for example with `kubectl get deployment -n cattle-fleet-system fleet-controller -o jsonpath='{.spec.template.spec.containers[0].image}'`
- Compare the version against the affected ranges: before `0.12`, `0.13.0` to `0.13.17`, `0.14.0` to `0.14.12`, `0.15.0` to `0.15.17`, `0.16.0` to `0.16.3`

## Fix

- Fleet: move to a version outside the affected ranges (the sources list the ranges above but do not name the fixed release for each line)

## Timeline

- 2026-10-30T16:31:25+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-104615

## From the sources

A security vulnerability was discovered in SUSE Rancher Fleet's cluster registration flow, in Fleet versions before 0.12, 0.13.0 up to 0.13.17, 0.14.0 up to 0.14.12, 0.15.0 up t o 0.15.17 and 0.16.0 up to 0.16.3. The cluster identity claimed by a registration request was accepted without being bound to the registration token that the request was made with. As a result, a registration request could be associated with a managed cluster that was originally registered with a different registration token.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_