CVE-2018-0434 in SD-WAN Solution
Summary
by MITRE
A vulnerability in the Zero Touch Provisioning feature of the Cisco SD-WAN Solution could allow an unauthenticated, remote attacker to gain unauthorized access to sensitive data by using an invalid certificate. The vulnerability is due to insufficient certificate validation by the affected software. An attacker could exploit this vulnerability by supplying a crafted certificate to an affected device. A successful exploit could allow the attacker to conduct man-in-the-middle attacks to decrypt confidential information on user connections to the affected software.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 03/30/2020
The vulnerability identified as CVE-2018-0434 resides within the Zero Touch Provisioning feature of Cisco's SD-WAN Solution, representing a critical security weakness that undermines the integrity of device authentication processes. This flaw specifically targets the certificate validation mechanisms employed by the affected software, creating a pathway for malicious actors to bypass legitimate authentication procedures. The vulnerability stems from inadequate certificate validation logic that fails to properly verify the authenticity and legitimacy of presented certificates, allowing attackers to exploit this weakness through carefully crafted malicious certificates.
The technical exploitation of this vulnerability occurs through a man-in-the-middle attack vector where an unauthenticated remote attacker can supply a forged certificate to an affected device during the provisioning process. This insufficient validation allows the malicious certificate to be accepted as legitimate, thereby compromising the entire security framework of the SD-WAN solution. The vulnerability directly relates to CWE-295 which addresses improper certificate validation, and aligns with ATT&CK technique T1046 for network service scanning and T1566 for credential harvesting through social engineering or network infiltration. When successfully exploited, the attacker gains unauthorized access to sensitive data flowing through the network connections managed by the affected devices.
The operational impact of this vulnerability extends beyond simple data theft, as it fundamentally compromises the security posture of entire SD-WAN deployments. Organizations utilizing Cisco SD-WAN solutions become vulnerable to comprehensive surveillance and data interception across their network infrastructure, potentially exposing confidential communications, user credentials, and business-critical information. The vulnerability affects the trust model of the entire SD-WAN ecosystem, as the compromised devices can no longer be trusted to properly authenticate connections and protect data integrity. This creates cascading security implications throughout the network, as compromised devices may serve as entry points for further lateral movement and privilege escalation attacks.
Mitigation strategies for CVE-2018-0434 should prioritize immediate patching of affected devices through Cisco's official security advisories and software updates. Network administrators must implement strict certificate management policies and establish robust certificate validation procedures that enforce proper certificate chain validation and hostname verification. The implementation of additional security controls such as network segmentation, enhanced monitoring of provisioning activities, and regular security assessments of SD-WAN components can help detect and prevent exploitation attempts. Organizations should also consider implementing certificate pinning mechanisms and establishing automated certificate lifecycle management processes to prevent the acceptance of unauthorized certificates. The vulnerability demonstrates the critical importance of proper certificate validation in network security infrastructure and highlights the need for continuous security auditing of authentication mechanisms within enterprise network solutions.