CVE-2026-92772 in Leantime
Summary
by MITRE • 09/16/2026
Leantime before 3.9.6 contains an authorization bypass vulnerability in the HTMX plugin install endpoint that lacks permission validation. Authenticated users with limited roles can install marketplace plugins and control arbitrary properties including identifier, version, and license key to deploy malicious plugins.
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Analysis
by VulDB Data Team • 09/16/2026
The identified security flaw resides within the Leantime application prior to version 3.9.6, specifically targeting the endpoint responsible for installing HTMX-based plugins from the official marketplace. This vulnerability constitutes a critical authorization bypass that stems directly from insufficient access control mechanisms on the server side. The core technical deficiency is the absence of permission validation when processing requests intended to install new extensions or modules into the system. In a properly secured architecture, any operation involving the modification of application state, such as installing software components, must be strictly gated by role-based access controls that verify whether the authenticated user possesses the necessary administrative privileges. However, in this specific implementation, the endpoint fails to enforce these checks, allowing any logged-in account, regardless of its assigned role or privilege level, to execute installation procedures.
This lack of validation enables attackers with low-privileged accounts to escalate their influence within the application environment significantly. By exploiting this flaw, an attacker can manipulate critical parameters associated with the plugin installation process, including the unique identifier, version number, and license key fields. These parameters are not merely cosmetic; they dictate which code is downloaded from the marketplace and how it is registered within the system's internal registry. The ability to control these properties allows a malicious actor to potentially bypass integrity checks or manipulate the licensing subsystem, although the primary risk lies in the deployment of arbitrary code under the guise of legitimate marketplace extensions.
The operational impact of this vulnerability is severe due to the nature of plugin architectures in web applications like Leantime. Plugins often operate with elevated privileges relative to standard user functions and may have access to sensitive data or system-level APIs. By deploying a maliciously crafted plugin, an attacker can achieve remote code execution within the context of the application server. This could lead to full compromise of the underlying infrastructure, including unauthorized access to project management data, client information, and internal communications stored by Leantime users. Furthermore, because the installation process involves downloading content from an external source controlled or influenced by the installer's inputs, there is a risk of supply chain contamination if the attacker can manipulate which version or variant of a plugin is fetched, potentially introducing backdoors that persist even after remediation efforts are initiated on other fronts.
From a classification perspective, this vulnerability aligns with CWE-269, Improper Privilege Management, as it allows users to perform actions beyond their intended permissions. It also maps closely to ATT&CK technique T1059, Command and Scripting Interpreter, via the execution of malicious plugin code, and potentially T1195, Supply Chain Compromise, if the attacker leverages the marketplace infrastructure itself. The failure represents a fundamental breakdown in the principle of least privilege, where authentication is present but authorization logic is missing for specific high-risk endpoints.
To mitigate this risk, organizations running Leantime must immediately upgrade to version 3.9.6 or later, which includes patches that enforce strict role-based access control on the plugin installation endpoint. Until an upgrade can be performed, administrators should restrict network-level access to the application if possible and monitor server logs for unusual patterns of plugin installations initiated by non-administrative accounts. Additionally, implementing a Web Application Firewall with rules targeting suspicious payloads in the license key or identifier fields may provide temporary relief against exploitation attempts that rely on malformed input structures. Regular audits of installed plugins and verification of their digital signatures can also help detect any malicious components introduced prior to patching.