CVE-2026-92073 in Firefox
Summary
by MITRE • 09/15/2026
Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 156 and Firefox ESR 153.3.
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Analysis
by VulDB Data Team • 09/15/2026
The identified security issue represents a critical privilege escalation flaw within the Enterprise Policies subsystem of Mozilla Firefox, specifically affecting versions prior to 156 and Firefox Extended Support Release (ESR) version 153.3. This vulnerability allows an attacker with limited user privileges or access to specific configuration files to elevate their permissions on the host system beyond what is intended by the operating system's security model. Enterprise Policies are designed to allow organizations to manage browser settings centrally, but a flaw in how these policies are parsed or applied can be exploited to execute arbitrary code or modify critical system states with elevated rights. This type of vulnerability falls under the Common Weakness Enumeration category CWE-269, which covers Improper Privilege Management, and is often associated with ATT&CK technique T1055, Process Injection, or T1078, Valid Accounts, depending on the specific exploitation vector used to trigger the escalation.
The technical root cause typically involves a failure in input validation or access control checks within the policy engine when processing configuration data. In many browser-based privilege escalation scenarios, this occurs because the application fails to properly sanitize inputs before applying them as system-level commands or configurations. An attacker could craft a malicious enterprise policy file that exploits this lack of sanitization. When the Firefox process loads these policies, it may inadvertently execute code in a context with higher privileges than the user running the browser session. This discrepancy between the intended security boundary and the actual execution environment creates an opportunity for lateral movement or complete system compromise if the attacker can influence the policy source, such as through a compromised network share, a malicious extension installation that modifies local configuration files, or social engineering tactics that trick a privileged user into loading a specific configuration.
The operational impact of this vulnerability is severe due to its potential to bypass standard security controls and grant an attacker full control over the affected system. Once privilege escalation is achieved, the attacker can install persistent malware, exfiltrate sensitive data stored in browser profiles or local storage, modify system configurations, and move laterally within a corporate network if Firefox is used as a primary tool for enterprise operations. This undermines the integrity of the endpoint security posture and violates the principle of least privilege that underpins modern operating systems. The risk is particularly acute in environments where centralized management tools are deployed, as attackers may target these infrastructure components to push malicious policies across multiple endpoints simultaneously, amplifying the blast radius of the exploit significantly beyond a single user session.
Mitigation strategies must prioritize immediate patching and configuration hardening. Organizations should update all instances of Firefox to version 156 or later, and ESR users to version 153.3 or higher, as these releases contain the necessary code fixes that address the input validation flaws within the Enterprise Policies component. In addition to updating software, administrators should enforce strict access controls on policy configuration files to ensure they can only be modified by authorized system accounts rather than standard user profiles. Implementing application whitelisting and monitoring for unusual process creation events associated with browser processes can help detect exploitation attempts in real time. Furthermore, regular audits of enterprise policies deployed across the network are essential to identify any unauthorized or malformed configurations that might indicate an attempt to exploit this vulnerability before it is patched on all endpoints.