CVE-2026-21423 in PowerScale OneFS
Summary
by MITRE • 03/04/2026
Dell PowerScale OneFS, versions prior to 9.10.1.6 and versions 9.11.0.0 through 9.12.0.1, contains an incorrect default permissions vulnerability. A high privileged attacker with local access could potentially exploit this vulnerability, leading to code execution, denial of service, elevation of privileges, and information disclosure.
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Analysis
by VulDB Data Team • 03/05/2026
The vulnerability identified as CVE-2026-21423 affects Dell PowerScale OneFS storage systems and represents a critical security flaw in the system's permission handling mechanisms. This issue specifically impacts versions prior to 9.10.1.6 and the affected range of 9.11.0.0 through 9.12.0.1, creating a persistent security risk for organizations relying on these storage platforms. The vulnerability stems from incorrect default permissions that fail to properly enforce access controls, creating potential attack vectors for malicious actors who have already gained local system access. According to CWE classification, this vulnerability aligns with CWE-276, which addresses incorrect permissions, making it a direct implementation of improper access control principles that form the foundation of secure system design.
The technical exploitation of this vulnerability requires a high-privileged attacker to already possess local access to the affected system, which significantly reduces the attack surface compared to remotely exploitable flaws. However, the severity of the potential impact makes this particularly dangerous as attackers who have achieved local access can leverage this weakness to escalate their privileges, execute arbitrary code, or cause denial of service conditions. The default permission settings fail to properly isolate system processes and user access, creating pathways for privilege escalation that can ultimately allow attackers to gain root-level access to the storage system. This flaw operates at the operating system level within the OneFS environment, affecting the core security architecture that governs how different system components interact with each other and with user requests.
The operational impact of CVE-2026-21423 extends beyond simple privilege escalation, as it can lead to complete system compromise and data exposure. Organizations using affected Dell PowerScale systems face potential data leakage through information disclosure mechanisms, where unauthorized access to system files, configuration data, or user information could occur. The denial of service component of this vulnerability can result in storage system unavailability, disrupting business operations and potentially causing significant financial impact. System administrators must consider that this vulnerability can be exploited to establish persistent access points within storage environments, making it particularly dangerous in enterprise settings where storage systems serve as critical infrastructure components. The attack pattern aligns with ATT&CK technique T1068, which covers 'Exploitation for Privilege Escalation', and T1499, covering 'Endpoint Denial of Service', demonstrating the comprehensive nature of the threat.
Mitigation strategies for this vulnerability require immediate system updates to the patched versions of Dell PowerScale OneFS, specifically versions 9.10.1.6 and later, as well as 9.11.0.2 and 9.12.0.2 or higher. Organizations should conduct comprehensive vulnerability assessments to identify systems running affected versions and prioritize patching activities based on risk assessment. Network segmentation and access control measures should be implemented to limit local system access, reducing the attack surface for potential exploitation. System monitoring should be enhanced to detect unusual privilege escalation attempts or abnormal system behavior that might indicate exploitation attempts. Additionally, organizations should review their access control policies and ensure proper principle of least privilege enforcement is maintained across all system components. The remediation process must include thorough testing of patches in controlled environments before deployment to production systems, ensuring that the security updates do not introduce compatibility issues with existing storage workflows and applications.