CVE-2026-91336 in Solaris
Summary
by MITRE • 10/21/2026
Vulnerability in the Oracle Solaris product of Oracle Systems (component: Utility). The supported version that is affected is 11.4. Easily exploitable vulnerability allows low privileged attacker with logon to the infrastructure where Oracle Solaris executes to compromise Oracle Solaris. While the vulnerability is in Oracle Solaris, attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in unauthorized creation, deletion or modification access to critical data or all Oracle Solaris accessible data. CVSS 3.1 Base Score 6.5 (Integrity impacts). CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N).
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Analysis
by VulDB Data Team • 10/21/2026
The identified vulnerability resides within the Utility component of Oracle Solaris version 11.4, representing a significant security flaw that compromises the integrity of the operating system environment. This issue is classified as an easily exploitable vulnerability that requires low-privileged access to the infrastructure where Oracle Solaris is executing. The attack vector for this weakness is local, meaning an attacker must already have valid logon credentials and basic access to the system before they can initiate exploitation. Despite requiring initial authentication, the ease of exploitation suggests a fundamental flaw in how the utility handles data or permissions, allowing a user with minimal privileges to escalate their impact beyond what should be possible under normal security policies.
The technical nature of this vulnerability centers on unauthorized modifications to critical data structures and system files. Successful exploitation enables an attacker to create, delete, or modify access controls for sensitive information stored within the Oracle Solaris environment. This capability directly undermines the integrity assurance mechanisms designed to protect operating system resources from tampering by non-administrative users. The flaw likely stems from improper validation of user inputs or insufficient separation of privileges when processing requests through the affected utility module. Such defects often arise when developers fail to enforce strict access control lists or boundary checks, allowing a low-privileged process to interact with higher-level system components in unintended ways.
The operational impact of this vulnerability extends beyond the immediate Oracle Solaris instance due to its potential for scope change. While the direct target is the operating system itself, the compromise can significantly affect additional products and services running on or connected to that infrastructure. If an attacker gains the ability to modify critical data or alter access permissions, they may disrupt service availability, steal sensitive information indirectly through modified configurations, or establish persistence mechanisms within the broader network environment. The CVSS 3.1 base score of 6.5 reflects a medium severity level, primarily driven by high integrity impacts while confidentiality and availability remain unaffected in this specific assessment vector. This scoring indicates that while data theft is not directly facilitated, the ability to alter system state poses substantial risk to organizational security posture.
From a classification perspective, this vulnerability aligns with CWE-269, which addresses Improper Privilege Management, as it allows a lower-privileged actor to perform actions reserved for higher privileges or critical system functions. It also relates closely to CWE-732, concerning Incorrect Permission Assignment for Critical Resource, given the unauthorized creation and modification of access rights. In terms of adversary behavior mapping under MITRE ATT&CK, this vulnerability facilitates techniques associated with Privilege Escalation on Linux and Unix systems, specifically those involving local exploitation of misconfigured services or utilities to gain elevated control over system resources.
Mitigation strategies should focus primarily on applying the latest security patches provided by Oracle for Solaris 11.4 immediately upon availability. Organizations must ensure that their patch management processes are agile enough to address medium-severity vulnerabilities promptly, as even low-privilege flaws can lead to significant lateral movement or data tampering if left unaddressed. In addition to patching, implementing strict least privilege principles is essential; administrators should review user accounts and group memberships to ensure no unnecessary local access exists for non-critical personnel. Network segmentation and monitoring solutions that detect anomalous file system changes or unexpected process executions can also help identify potential exploitation attempts in real-time, providing an additional layer of defense against this type of integrity-focused attack.