CVE-2021-1382 in IOS XE SD-WAN
Summary
by MITRE • 03/25/2021
A vulnerability in the CLI of Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to inject arbitrary commands to be executed with root privileges on the underlying operating system. This vulnerability is due to insufficient input validation on certain CLI commands. An attacker could exploit this vulnerability by authenticating to the device and submitting crafted input to the CLI. The attacker must be authenticated as an administrative user to execute the affected commands. A successful exploit could allow the attacker to execute commands with 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 • 04/04/2021
This vulnerability exists within the command line interface of Cisco IOS XE SD-WAN Software, representing a critical privilege escalation flaw that enables authenticated local attackers to execute arbitrary commands with root privileges. The vulnerability stems from inadequate input validation mechanisms within specific CLI command handlers, creating a pathway for command injection attacks. The flaw specifically affects the underlying operating system of the device, allowing attackers to bypass normal security boundaries and gain elevated system access. According to CWE-77 and CWE-78 classifications, this represents a command injection vulnerability that permits arbitrary code execution through improperly validated user inputs. The security implications are severe as the attack requires only local authentication, eliminating the need for external network access or complex exploitation techniques. This vulnerability directly aligns with attack patterns described in the MITRE ATT&CK framework under T1059.001 for Command and Scripting Interpreter, where adversaries leverage legitimate system tools to execute malicious commands. The affected CLI commands lack proper sanitization of user-supplied parameters, allowing crafted input to be interpreted as system commands rather than mere data inputs. The authentication requirement of administrative privileges provides a minimum barrier, though this is insufficient to prevent exploitation given the severity of potential impact. Attackers exploiting this vulnerability can execute arbitrary code with full system privileges, potentially leading to complete system compromise, data exfiltration, or persistent access through rootkit installation.
The operational impact of this vulnerability extends beyond immediate privilege escalation to encompass broader network security implications. Once exploited, attackers can manipulate network configurations, establish backdoors, or disable security controls within the SD-WAN infrastructure. The vulnerability affects Cisco IOS XE SD-WAN deployments where administrative access has been compromised, potentially through credential theft, insider threats, or other authentication bypass techniques. The root privilege execution capability enables attackers to modify system files, install malicious software, or access sensitive network data that would otherwise be protected by normal access controls. This vulnerability particularly impacts enterprise networks relying on SD-WAN solutions for branch office connectivity, as compromised devices can serve as attack vectors for lateral movement throughout the network. The security posture of affected organizations deteriorates significantly since the vulnerability can be exploited by insiders or compromised administrative accounts without requiring external network access. Network segmentation benefits may be undermined as attackers can leverage the elevated privileges to traverse network boundaries or access systems that should be isolated from the compromised device. The impact is amplified in environments where SD-WAN devices serve as central points of network control and management, potentially enabling attackers to disrupt network services or manipulate traffic routing.
Mitigation strategies for this vulnerability must address both immediate remediation and long-term security improvements. Cisco has released patches and software updates to address this vulnerability, requiring organizations to apply the latest security fixes to all affected devices. Network administrators should implement strict access control measures, including multi-factor authentication for administrative accounts and regular credential rotation policies. The principle of least privilege should be enforced by limiting administrative access to only necessary personnel and using separate accounts for different administrative functions. Network monitoring solutions should be enhanced to detect anomalous command execution patterns or unusual administrative activities that might indicate exploitation attempts. Security awareness training for network administrators is essential to prevent credential compromise and social engineering attacks that could lead to exploitation. Regular security assessments and vulnerability scanning should include verification of patch compliance and configuration reviews to ensure proper input validation is in place. Organizations should implement network access controls to restrict administrative access to specific IP addresses or network segments and establish logging requirements for all administrative activities. The implementation of intrusion detection systems capable of identifying command injection attempts and network segmentation strategies can help limit the potential impact of successful exploitation. Additionally, regular security audits should verify that CLI configurations properly sanitize user inputs and that administrative access is appropriately restricted to prevent unauthorized privilege escalation.