CVE-2026-18874

Description

A flaw was found in volsync-addon-controller. This vulnerability allows an attacker to inject malicious YAML (Yet Another Markup Language) code into the OpenShift Lifecycle Manager (OLM) Subscription resource. This is due to improper escaping of annotation values when they are rendered into YAML. Successful exploitation could lead to unauthorized modification or control over OLM Subscription configurations, potentially impacting software management within the cluster. This issue primarily affects systems where the 'volsync-addon-deploy-type: olm' annotation is explicitly enabled.

Statement

This Moderate flaw in volsync-addon-controller allows YAML injection into the OLM Subscription resource. Exploitation requires the volsync-addon-deploy-type: olm annotation to be explicitly configured, which is not the default setting in Red Hat Advanced Cluster Management for Kubernetes since ACM 2.13, thereby limiting the attack surface.

Mitigation

To mitigate this vulnerability, ensure that the `volsync-addon-deploy-type` annotation is not explicitly set to `olm`. The default Helm deployment type for volsync-addon-controller in Red Hat Advanced Cluster Management for Kubernetes (since ACM 2.13) is not affected by this flaw.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score6.2N/A6.2
Attack VectorNetworkN/ANetwork
Attack ComplexityHighN/AHigh
Privileges RequiredHighN/AHigh
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityLowN/ALow
Integrity ImpactHighN/AHigh
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:H/A:H

cve.org: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:H/A:H

Red Hat CVSS v3 Score Explanation

PR:L→PR:H: modifying ManagedClusterAddOn annotations on the ACM hub requires cluster-admin or addon-management RBAC, not low-privilege access

Understanding the Weakness (CWE)

Access Control

Technical Impact: Bypass Protection Mechanism

In some cases, injectable code controls authentication; this may lead to a remote vulnerability.

Access Control

Technical Impact: Gain Privileges or Assume Identity

Injected code can access resources that the attacker is directly prevented from accessing.

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

When a product allows a user's input to contain code syntax, it might be possible for an attacker to craft the code in such a way that it will alter the intended control flow of the product. As a result, code injection can often result in the execution of arbitrary code. Code injection attacks can also lead to loss of data integrity in nearly all cases, since the control-plane data injected is always incidental to data recall or writing.

Non-Repudiation

Technical Impact: Hide Activities

Often the actions performed by injected control code are unlogged.

Frequently Asked Questions

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