CVE-2024-20350 in Digital Network Architecture Center
Summary
by MITRE • 09/25/2024
A vulnerability in the SSH server of Cisco Catalyst Center, formerly Cisco DNA Center, could allow an unauthenticated, remote attacker to impersonate a Cisco Catalyst Center appliance.
This vulnerability is due to the presence of a static SSH host key. An attacker could exploit this vulnerability by performing a machine-in-the-middle attack on SSH connections, which could allow the attacker to intercept traffic between SSH clients and a Cisco Catalyst Center appliance. A successful exploit could allow the attacker to impersonate the affected appliance, inject commands into the terminal session, and steal valid user credentials.
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Analysis
by VulDB Data Team • 07/30/2025
The vulnerability identified as CVE-2024-20350 represents a critical security flaw in Cisco Catalyst Center's SSH server implementation that fundamentally undermines the integrity of remote access communications. This issue stems from the improper configuration of the Secure Shell service where a static SSH host key is embedded within the appliance software, creating a persistent cryptographic weakness that persists across all instances of the affected product. The vulnerability affects Cisco Catalyst Center appliances running specific software versions and represents a significant risk to network infrastructure security. The presence of a static host key violates fundamental security principles of asymmetric cryptography where unique key pairs should be generated for each device instance to prevent impersonation attacks. This flaw directly enables man-in-the-middle attack scenarios where adversaries can establish fraudulent connections that appear legitimate to SSH clients, effectively breaking the trust model that SSH protocols are designed to maintain.
The technical exploitation of this vulnerability requires minimal prerequisites and can be executed by any unauthenticated remote attacker with network access to the target appliance. The static SSH host key creates a predictable cryptographic signature that attackers can leverage to intercept and manipulate SSH communications between legitimate clients and the affected appliance. When SSH clients connect to the vulnerable appliance, they cannot distinguish between the authentic device and an attacker's impostor, as the cryptographic fingerprint remains constant across all deployments. This characteristic enables attackers to perform session hijacking operations where they can inject malicious commands into active terminal sessions, capture user credentials, and potentially escalate privileges within the network management environment. The vulnerability specifically targets the SSH protocol's host authentication mechanism, which relies on public key cryptography to verify server identity. The absence of unique host key generation means that attackers can simply replicate the known static key to establish trust relationships with SSH clients, fundamentally compromising the security assurances that SSH provides.
The operational impact of this vulnerability extends beyond simple credential theft to encompass complete compromise of network management infrastructure. Successful exploitation allows attackers to impersonate the legitimate Cisco Catalyst Center appliance, enabling them to manipulate network configurations, access sensitive operational data, and potentially gain unauthorized control over network devices managed through the platform. The stolen credentials could provide attackers with administrative access to the entire network management system, potentially exposing the organization's entire network infrastructure to further compromise. This vulnerability particularly affects organizations that rely heavily on Cisco Catalyst Center for network operations and monitoring, as it undermines the trust relationships that are essential for secure remote management. The attack vector requires no prior authentication credentials and can be executed from any network location where the appliance is accessible, making it extremely difficult to defend against through traditional network segmentation approaches. The implications for network security are severe as this vulnerability essentially provides attackers with a backdoor into the core network management infrastructure, potentially enabling them to conduct reconnaissance, establish persistence, and execute advanced attacks against the underlying network fabric.
Organizations affected by this vulnerability should immediately implement mitigations including updating to the latest software releases that address the static host key issue through proper key generation mechanisms. The recommended approach involves applying Cisco's security patches that regenerate unique SSH host keys for each appliance instance, thereby eliminating the static key vulnerability. Network administrators should also consider implementing additional security controls such as SSH key pinning, network segmentation, and monitoring for unusual SSH connection patterns that might indicate impersonation attempts. Organizations should conduct comprehensive vulnerability assessments to identify all instances of affected Cisco Catalyst Center appliances and ensure proper patch management procedures are in place. The mitigation strategy should include monitoring SSH connection logs for anomalous host key changes or connection attempts that might indicate an active attack. This vulnerability highlights the importance of proper cryptographic key management practices and demonstrates how a single configuration flaw can compromise the entire security posture of network management systems. The issue aligns with CWE-310, which addresses cryptographic weaknesses, and represents a specific instance of improper key management that violates fundamental security principles of authentication and integrity protection. From an ATT&CK perspective, this vulnerability maps to techniques involving credential access and defense evasion, as attackers can use the impersonation capability to avoid detection while accessing sensitive network management resources.