A vulnerability in the key-based SSH authentication mechanism of Cisco Umbrella Virtual Appliance (VA) could allow an unauthenticated, remote attacker to impersonate a VA. This vulnerability is due to the presence of a static SSH host key. An attacker could exploit this vulnerability by performing a man-in-the-middle attack on an SSH connection to the Umbrella VA. A successful exploit could allow the attacker to learn the administrator credentials, change configurations, or reload the VA. Note: SSH is not enabled by default on the Umbrella VA.
This vulnerability has been assigned a CVSS score of 7.5, classified as high severity. The potential impact includes significant risks to confidentiality, integrity, and availability, making it critical for organizations using Cisco Umbrella to address this issue immediately.
The exploitation status indicates that there are currently no known exploits or public proof of concept (PoC) available for this vulnerability, which suggests that while the risk is present, active exploitation is not yet confirmed. However, organizations should prioritize patching immediately.
With the potential for attackers to gain unauthorized access and manipulate critical configurations, organizations must act swiftly to mitigate risks associated with this vulnerability.
Vulnerability Details
The vulnerability in question relates to the Cisco Umbrella Virtual Appliance's SSH authentication process, attributed to a static SSH host key. This issue is classified under CWE-321 (Use of Hard-coded Cryptographic Key) and CWE-798 (Use of Hard-coded Credentials).
The CVSS score from the NVD indicates a base score of 8.1, emphasizing the high severity of this vulnerability. It is critical for organizations to understand the implications of this vulnerability, especially in environments where the Umbrella VA is deployed.
Technical Analysis
The root cause of this vulnerability is the use of a static SSH host key, which can be exploited through a man-in-the-middle attack. The attack vector is network-based, and the complexity is assessed as high, requiring user interaction for successful exploitation.
The attack scenario necessitates that the attacker be able to intercept the SSH connection, thus requiring no privileges or prior authentication, but does require user interaction. Should the attacker succeed, the impacts could lead to high confidentiality, integrity, and availability losses.
Risk & Impact Analysis
Risk to organizations includes unauthorized access to sensitive administrative credentials, which could lead to changes in configurations or reloading of the appliance, severely impacting service availability and data integrity.
Given the current CVSS score, organizations should assess the urgency of addressing this vulnerability as high, prioritizing it in their patch management cycles.
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The affected versions include all Cisco Umbrella products prior to version 3.3.2. Organizations should verify their installations and ensure they are running an updated version to mitigate this vulnerability.
Mitigation & Remediation
Organizations should address this vulnerability by applying the latest patches from Cisco. It is crucial to upgrade to the latest version of the Cisco Umbrella VA to eliminate the static SSH host key issue.
In addition, organizations should consider implementing network controls to restrict SSH access and monitor logs for any unusual activities that could indicate attempts to exploit this vulnerability.
Continuous penetration testing can also help identify any residual vulnerabilities after remediation.
Detection Guidance
To detect potential exploitation of this vulnerability, organizations should monitor SSH connection logs for any unauthorized access attempts and behavioral anomalies that may indicate man-in-the-middle attacks.
Additionally, network signatures should be developed to identify suspicious activity related to SSH connections.
AppSecure Threat Intelligence Insight
This vulnerability highlights the critical need for secure SSH configurations in network devices. The presence of a static SSH host key poses significant risks, and organizations must remain vigilant in monitoring and securing their network infrastructures.
Security teams should review their SSH practices and consider adopting dynamic key management solutions to prevent similar issues in the future. Organizations can learn from this vulnerability by implementing comprehensive vulnerability management programs that include regular audits and updates to security configurations.
Furthermore, organizations can enhance their defenses by engaging in regular penetration testing to validate the effectiveness of their security measures.
By prioritizing security and being proactive in remediation efforts, organizations can better protect themselves against emerging threats.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
.webp)