CVE-2018-0348 in SD-WAN Solution
Summary
by MITRE
A vulnerability in the CLI of the Cisco SD-WAN Solution could allow an authenticated, remote attacker to inject arbitrary commands that are executed with root privileges. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by authenticating to the device and submitting malicious input to the load command within the VPN subsystem. The attacker must be authenticated to access the affected CLI parameter. A successful exploit could allow an attacker to execute commands with root privileges. This vulnerability affects the following Cisco products if they are running a release of the Cisco SD-WAN Solution prior to Release 18.3.0: vBond Orchestrator Software, vEdge 100 Series Routers, vEdge 1000 Series Routers, vEdge 2000 Series Routers, vEdge 5000 Series Routers, vEdge Cloud Router Platform, vManage Network Management Software, vSmart Controller Software. Cisco Bug IDs: CSCvi69866.
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Analysis
by VulDB Data Team • 03/08/2020
The vulnerability identified as CVE-2018-0348 represents a critical command injection flaw within the Cisco SD-WAN Solution CLI interface that fundamentally undermines the security posture of affected network infrastructure. This vulnerability resides in the VPN subsystem where the load command fails to properly validate user input, creating a pathway for authenticated attackers to execute arbitrary code with the highest possible privileges. The flaw specifically targets the command line interface of Cisco's software-defined wide area networking solution, which is designed to manage and optimize enterprise network connections across distributed environments. The vulnerability affects a broad range of Cisco SD-WAN products including vBond orchestrators, various vEdge router series, vManage network management software, and vSmart controllers, making it particularly dangerous due to its widespread impact across the SD-WAN ecosystem.
The technical exploitation of this vulnerability leverages insufficient input validation mechanisms that should have prevented malicious command injection attempts. When an authenticated attacker submits crafted input to the load command within the VPN subsystem, the system fails to properly sanitize or validate the input before processing it, leading to arbitrary code execution with root privileges. This type of vulnerability falls under CWE-74 which specifically addresses "Improper Neutralization of Special Elements in Output Used by a Downstream Component," and more broadly aligns with CWE-94 which covers "Improper Control of Generation of Code ('Code Injection')." The attack vector requires authentication to access the CLI, meaning that an attacker must first establish valid credentials, but once authenticated, the privilege escalation to root level execution becomes possible, effectively providing complete system compromise.
The operational impact of this vulnerability extends far beyond simple privilege escalation as it allows attackers to gain complete control over the affected SD-WAN infrastructure components. Since the vBond orchestrator, vEdge routers, and other management components are critical to network operations, unauthorized access could result in complete network disruption, data exfiltration, or the establishment of persistent backdoors within enterprise networks. The vulnerability affects multiple product lines including the vEdge 100, 1000, 2000, and 5000 series routers, along with the vManage and vSmart controllers, creating a substantial attack surface that could impact large enterprise networks. The fact that this vulnerability requires only authenticated access but provides root privileges makes it particularly attractive to attackers who may have gained initial access through other means such as credential theft or social engineering.
Mitigation strategies for CVE-2018-0348 primarily center on upgrading to Cisco SD-WAN Solution Release 18.3.0 or later, which contains the necessary patches to address the input validation deficiencies. Network administrators should immediately implement this upgrade across all affected devices to prevent exploitation. Additional defensive measures include implementing strict access controls and monitoring for unusual CLI activity, particularly around the load command within VPN subsystems. The vulnerability's classification under the ATT&CK framework would place it within the Privilege Escalation tactic, specifically under techniques that involve command injection and code execution. Organizations should also consider implementing network segmentation to limit the potential impact of successful exploitation and establish robust monitoring protocols to detect unauthorized CLI access patterns. Given the critical nature of SD-WAN infrastructure, continuous vulnerability assessment and patch management should be prioritized to maintain protection against similar vulnerabilities in the future.