CVE-2020-9355 in NetworkManager-ssh
Summary
by MITRE
danfruehauf NetworkManager-ssh before 1.2.11 allows privilege escalation because extra options are mishandled.
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Analysis
by VulDB Data Team • 04/02/2024
The CVE-2020-9355 vulnerability affects the NetworkManager-ssh package version 1.2.11 and earlier, representing a critical privilege escalation flaw within the NetworkManager infrastructure. This vulnerability stems from improper handling of extra options within the ssh plugin component, creating a security gap that allows unauthorized users to gain elevated privileges on systems running affected NetworkManager versions. The issue specifically manifests when NetworkManager processes additional SSH configuration options, leading to potential arbitrary code execution with root privileges. The flaw exists in the way the system manages command-line arguments and configuration parameters, creating an environment where malicious input can be interpreted and executed with elevated permissions.
The technical root cause of this vulnerability lies in the insecure processing of user-supplied parameters within the ssh plugin's option handling mechanism. When extra SSH options are configured through NetworkManager, the system fails to properly sanitize or validate these inputs before incorporating them into system commands. This improper input handling creates a path for privilege escalation attacks where an attacker can inject malicious commands that execute with the privileges of the NetworkManager process, typically running with root access. The vulnerability operates under the broader category of command injection flaws, which are classified under CWE-78 in the Common Weakness Enumeration framework. This weakness specifically relates to the improper execution of system commands with untrusted input, allowing attackers to manipulate the execution flow of the underlying system services.
The operational impact of CVE-2020-9355 extends beyond simple privilege escalation to encompass potential system compromise and data exposure. An attacker exploiting this vulnerability can execute arbitrary commands with root privileges, potentially leading to complete system takeover, data exfiltration, or persistent backdoor installation. The vulnerability is particularly concerning in environments where NetworkManager is actively managing SSH connections, as it provides a direct path for attackers to escalate their privileges without requiring additional attack vectors. Systems running affected versions of NetworkManager-ssh are at risk of unauthorized access and manipulation, especially in enterprise environments where SSH connections are frequently managed through centralized network configuration tools. The attack surface is broadened by the fact that this vulnerability can be exploited through legitimate NetworkManager configuration interfaces, making detection more challenging.
Mitigation strategies for CVE-2020-9355 primarily focus on updating to the patched version of NetworkManager-ssh, specifically version 1.2.11 or later, which addresses the improper option handling through proper input validation and sanitization. System administrators should immediately implement this update across all affected systems and verify that no unauthorized configuration changes have been made. Additionally, implementing network segmentation and access controls can help limit the potential impact of exploitation by restricting access to NetworkManager configuration interfaces. Security monitoring should be enhanced to detect unusual NetworkManager activities and configuration changes that might indicate exploitation attempts. The vulnerability aligns with ATT&CK technique T1068 which covers privilege escalation through malicious configuration, and T1059 which covers execution through command and scripting interpreters. Organizations should also consider implementing principle of least privilege for NetworkManager services and regularly audit SSH configurations to prevent exploitation through misconfigured options. Patch management processes should be strengthened to ensure rapid deployment of security updates across all network infrastructure components.