CVE-2020-3595 in SD-WAN
Summary
by MITRE • 11/07/2020
A vulnerability in Cisco SD-WAN Software could allow an authenticated, local attacker to elevate privileges to root group on the underlying operating system. The vulnerability is due to incorrect permissions being set when the affected command is executed. An attacker could exploit this vulnerability by executing the affected command on an affected system. A successful exploit could allow the attacker to gain root privileges.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 12/03/2020
The vulnerability identified as CVE-2020-3595 represents a critical privilege escalation flaw within Cisco SD-WAN Software that directly compromises system integrity and access controls. This vulnerability specifically affects the underlying operating system's permission model, creating a pathway for authenticated local attackers to escalate their privileges to the root group level. The flaw resides in the improper handling of file and command execution permissions, which violates fundamental security principles of least privilege and mandatory access controls. Such vulnerabilities are particularly dangerous because they require minimal attack vectors while providing maximum system compromise potential, making them highly attractive targets for both malicious actors and red teams conducting security assessments.
The technical implementation of this vulnerability stems from incorrect permission settings that are established when specific commands are executed within the affected software environment. This misconfiguration creates a persistent security weakness that allows local users with valid authentication credentials to execute malicious payloads that would normally be restricted to privileged system operations. The vulnerability operates at the operating system level, bypassing application-level security controls and directly manipulating the permission model that governs user access to system resources. This type of flaw aligns with CWE-276, which addresses improper permissions and access control mechanisms, and demonstrates how insufficient privilege separation can lead to complete system compromise. The attack vector requires only local authentication, making it particularly concerning as it can be exploited from within the system itself rather than requiring external network access or complex social engineering.
The operational impact of CVE-2020-3595 extends far beyond simple privilege escalation, as it fundamentally undermines the security posture of any organization relying on Cisco SD-WAN solutions. Once an attacker achieves root-level access, they can manipulate system configurations, install persistent backdoors, exfiltrate sensitive data, and disable security controls without detection. This vulnerability directly violates the principle of defense in depth by creating an inherent weakness that bypasses multiple layers of security controls. Organizations utilizing affected Cisco SD-WAN software face significant risk of data breaches, system compromise, and potential lateral movement throughout their network infrastructure. The vulnerability's presence also impacts compliance requirements, as it creates audit trail gaps and violates security frameworks such as NIST SP 800-53 controls related to access control and system integrity. Attackers leveraging this vulnerability can potentially maintain persistent access for extended periods, making it particularly dangerous for environments where continuous monitoring and detection are critical.
Mitigation strategies for CVE-2020-3595 must address both immediate remediation and long-term security posture improvements. Organizations should prioritize applying Cisco's official security patches and updates as soon as they become available, as these typically include corrected permission settings and privilege enforcement mechanisms. Network segmentation and access control measures should be strengthened to limit local user privileges and reduce the attack surface available to potential exploiters. Regular security auditing and monitoring of system permissions should be implemented to detect anomalous privilege escalation attempts, with particular attention to command execution patterns and user access logs. The vulnerability highlights the importance of implementing the principle of least privilege and maintaining regular security assessments of all system components. Organizations should also consider implementing additional security controls such as privileged access management solutions, enhanced logging and monitoring, and regular penetration testing to identify similar permission-based vulnerabilities. The remediation process should include comprehensive system verification to ensure that no malicious modifications were made during the exploitation phase and that all system integrity controls remain functional.