CVE-2020-3219 in IOS XE
Summary
by MITRE
A vulnerability in the web UI of Cisco IOS XE Software could allow an authenticated, remote attacker to inject and execute arbitrary commands with administrative privileges on the underlying operating system of an affected device. The vulnerability is due to insufficient validation of user-supplied input to the web UI. An attacker could exploit this vulnerability by submitting crafted input to the web UI. A successful exploit could allow an attacker to execute arbitrary commands with administrative privileges on an affected device.
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Analysis
by VulDB Data Team • 10/21/2020
The vulnerability identified as CVE-2020-3219 represents a critical command injection flaw within the web user interface of Cisco IOS XE Software, a widely deployed network operating system. This vulnerability specifically targets the input validation mechanisms that protect the web UI from malicious user input, creating a pathway for authenticated remote attackers to escalate their privileges and execute arbitrary code on the underlying operating system. The flaw exists in the software's handling of user-supplied data within the web interface, where insufficient sanitization allows attackers to bypass normal security controls and gain administrative access to network devices.
The technical exploitation of this vulnerability requires an attacker to possess valid authentication credentials for the web UI, which significantly reduces the attack surface but does not eliminate the risk entirely. The vulnerability stems from inadequate input validation procedures that fail to properly sanitize or filter user-supplied parameters before processing them within the system's command execution pathways. This weakness aligns with CWE-74, which describes improper neutralization of special elements used in data queries, and specifically relates to CWE-94, which addresses the execution of arbitrary code or commands. The flaw enables attackers to inject malicious commands that are then executed with the highest privileges available on the device, effectively granting them complete control over the network infrastructure.
The operational impact of this vulnerability extends far beyond simple privilege escalation, as it provides attackers with the ability to manipulate network configurations, access sensitive data, and potentially disrupt network services. Network administrators face significant risk when this vulnerability is exploited, as it allows attackers to modify routing tables, disable security features, or establish backdoor access points within the network infrastructure. The attack vector is particularly concerning because it leverages the web UI, which is commonly used for routine network management tasks, making legitimate administrative access a potential entry point for malicious actors. This vulnerability directly impacts the CIA triad by compromising confidentiality, integrity, and availability of network services, as demonstrated by the ATT&CK framework's technique T1059.001 for command and scripting interpreter and T1566.001 for valid accounts.
Mitigation strategies for CVE-2020-3219 should prioritize immediate software patching through Cisco's official security advisories, which typically provide specific fixes for the input validation issues. Organizations must implement comprehensive network segmentation and access control measures to limit the potential impact of successful exploitation, including restricting web UI access to trusted administrative networks. Additional protective measures include implementing network monitoring solutions to detect unusual command execution patterns and establishing strict credential management policies that enforce multi-factor authentication for administrative access. Regular security audits and vulnerability assessments should be conducted to identify similar weaknesses in other network components, while network administrators should maintain detailed logging of all web UI activities to facilitate incident response and forensic analysis. The vulnerability underscores the importance of maintaining up-to-date security patches and implementing defense-in-depth strategies that reduce the attack surface of critical network infrastructure components.