GitHub Advisoryadvisory · Go

GHSA-8w87-58w6-hfv8 Rancher doesn't properly sanitize credentials in cluster template answers

CRITICAL Published 2026-03-03 Modified 2026-03-03 Official page ↗
Aliases
CVE-2021-36783
Ecosystem
Go
Packages
github.com/rancher/rancher
Severity
Critical
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Weaknesses
CWE-200, CWE-312, CWE-522
Reviewed
2026-03-03

Affected packages

• Go github.com/rancher/rancher: >= 2.5.0, < 2.5.13 → fixed in 2.5.13 • Go github.com/rancher/rancher: >= 2.6.0, < 2.6.4 → fixed in 2.6.4

Description

Impact It was discovered that in Rancher versions up to and including 2.5.12 and 2.6.3 there is a failure to properly sanitize credentials in cluster template answers. This failure can lead to plaintext storage and exposure of credentials, passwords and API tokens. The exposed credentials are visible in Rancher to authenticated `Cluster Owners`, `Cluster Members`, `Project Owners` and `Project Members` on the endpoints `/v1/management.cattle.io.clusters`, `/v3/clusters` and `/k8s/clusters/local/apis/management.cattle.io/v3/clusters`. Sensitive fields are now stripped from `Clusters` objects before the object is stored. For objects that existed before this security fix, a one-time migration happens on startup. Important: • It is highly advised to review for potential leaked credentials in this scenario, and to change them if deemed necessary. • The final impact severity for confidentiality, integrity and availability is dependent on the permissions that the leaked credentials have on their own services. Patches Patched versions include releases 2.5.13, 2.6.4 and later versions. Workarounds Limit access in Rancher to trusted users. There is not a direct mitigation besides upgrading to the patched Rancher versions. Important: It is highly advised to review for potential leaked credentials in this scenario, and to change them if deemed necessary. For more information If you have any questions or comments about this advisory: • Reach out to SUSE Rancher Security team for security related inquiries. • Open an issue in Rancher repository. • Verify our support matrix and product support lifecycle.

Related

Alias · CVE (1)

  • CVE-2021-36783 A Insufficiently Protected Credentials vulnerability in SUSE Rancher allows authenticated Cluster Owners, Cluster Members, Project Owners… vulnerability

Weakness · CWE (3)

  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor weakness
  • CWE-312 Cleartext Storage of Sensitive Information weakness
  • CWE-522 Insufficiently Protected Credentials weakness

References