9.9
CRITICAL CVSS 3.1
CVE-2026-10090
Multicluster-operators-subscription: multicluster-operators-subscription: namespace edit user can deploy cluster-scoped clusterrolebinding and become cluster-admin via application subscription
Description

A flaw was found in the Application Subscription controller (multicluster-operators-subscription) of Red Hat Advanced Cluster Management for Kubernetes (ACM). A user with namespace-scoped "edit" privileges in an ACM hub namespace can create a Channel resource pointing to a Helm repository they control and a Subscription resource referencing it. The app-subscription controller fetches and applies the Helm chart contents with its own elevated authority, without verifying whether the subscription creator holds the "open-cluster-management:subscription-admin" role and without restricting applied resources to the subscription namespace. This allows the attacker to include cluster-scoped resources in the Helm chart, such as a ClusterRoleBinding granting the attacker's ServiceAccount the "cluster-admin" ClusterRole. Successful exploitation results in full cluster-admin privilege escalation. This contradicts the ACM documentation which states that non-subscription-admin users should have resources deployed into the subscription namespace only.

INFO

Published Date :

Aug. 5, 2026, 9:18 a.m.

Last Modified :

Aug. 5, 2026, 3:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-10090 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Redhat advanced_cluster_management_for_kubernetes
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 CRITICAL 53f830b8-0a3f-465b-8143-3b8a9948e749
CVSS 3.1 CRITICAL [email protected]
Solution
Escalate privileges by restricting resource application and validating user roles.
  • Validate subscription creator role before applying resources.
  • Restrict applied resources to the subscription namespace.
  • Update the application subscription controller.
  • Review ACM documentation for role requirements.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-10090.

URL Resource
https://access.redhat.com/security/cve/CVE-2026-10090
https://bugzilla.redhat.com/show_bug.cgi?id=2483292
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-10090 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-10090 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-10090 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 05, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-10090', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-05T13:49:40.960456Z'}
  • New CVE Received by [email protected]

    Aug. 05, 2026

    Action Type Old Value New Value
    Added Affected [{'cpes': ['cpe:/a:redhat:acm:2'], 'vendor': 'Red Hat', 'product': 'Red Hat Advanced Cluster Management for Kubernetes 2', 'packageName': 'rhacm2/multicluster-operators-subscription-rhel9', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}]
    Added Description A flaw was found in the Application Subscription controller (multicluster-operators-subscription) of Red Hat Advanced Cluster Management for Kubernetes (ACM). A user with namespace-scoped "edit" privileges in an ACM hub namespace can create a Channel resource pointing to a Helm repository they control and a Subscription resource referencing it. The app-subscription controller fetches and applies the Helm chart contents with its own elevated authority, without verifying whether the subscription creator holds the "open-cluster-management:subscription-admin" role and without restricting applied resources to the subscription namespace. This allows the attacker to include cluster-scoped resources in the Helm chart, such as a ClusterRoleBinding granting the attacker's ServiceAccount the "cluster-admin" ClusterRole. Successful exploitation results in full cluster-admin privilege escalation. This contradicts the ACM documentation which states that non-subscription-admin users should have resources deployed into the subscription namespace only.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
    Added CWE CWE-267
    Added Reference https://access.redhat.com/security/cve/CVE-2026-10090
    Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2483292
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.