Description

Dell SCG 5.0 Appliance versions prior to 5.36.00.16 and Dell SCG 5.0 Application versions prior to 5.36.00.00, contains an Improper Validation of Certificate with Host Mismatch vulnerability. An unauthenticated attacker with remote access could potentially exploit this vulnerability, leading to protection mechanism bypass.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "4.8",
  "pubDate": "2026-09-07T16:17:29.563Z",
  "pubdate": "2026-09-07T16:17:29.563Z",
  "executiveSummary": "Dell Secure Connect Gateway (SCG) 5.0 Appliance and Application editions are susceptible to a security vulnerability involving Improper Validation of Certificate with Host Mismatch.\nThis flaw allows an unauthenticated, remote attacker to bypass critical protection mechanisms during the TLS/SSL handshake process.\nThe vulnerability resides in the way the affected systems handle identity verification when establishing encrypted connections.\nBy failing to correctly validate the host identity against the provided X.509 certificate, the application becomes vulnerable to Man-in-the-Middle (MitM) attacks.\nSuccessful exploitation enables an attacker to intercept, inspect, or modify sensitive data transmitted between the gateway and its endpoints.\nThe risk is significant as it undermines the integrity and confidentiality of secure communications within the administrative environment.\nAffected products include Dell SCG 5.0 Appliance versions prior to 5.36.00.16 and Dell SCG 5.0 Application versions prior to 5.36.00.00.",
  "technicalDetails": "The root cause of this vulnerability is a failure in the cryptographic verification logic where the implementation of host identity checking against the presented TLS certificate is insufficient. In standard secure communication protocols, a client must verify that the Common Name (CN) or Subject Alternative Name (SAN) of the server's certificate matches the hostname or IP address of the target server. In the affected Dell SCG versions, the validation logic fails to enforce this correlation properly, leading to a Host Mismatch vulnerability.\nAn unauthenticated attacker positioned as a Man-in-the-Middle can exploit this by presenting a fraudulent or arbitrary certificate during the TLS handshake. Because the application logic does not strictly validate the hostname binding, it erroneously trusts the connection, effectively bypassing the security controls intended to authenticate the remote peer.\nThe attack flow proceeds as follows: First, the attacker intercepts the network traffic between the Dell SCG appliance and the legitimate endpoint. Second, when the SCG initiates a connection, the attacker intercepts the request and injects their own malicious TLS certificate. Third, the SCG appliance performs an incomplete certificate check; while it may verify that the certificate is cryptographically signed, it fails to perform a rigorous host identity check. Fourth, the SCG establishes the secure channel with the attacker’s machine, believing it to be the legitimate target. Finally, the attacker acts as a transparent proxy, decrypting traffic, performing data inspection or injection, and re-encrypting the data before passing it to the intended destination.\nThis vulnerability is particularly severe because it does not require authentication or elevated privileges, making it accessible to any actor with network proximity or control over the routing path. The lack of proper certificate host validation compromises the entire trust model of the SCG communications. Post-exploitation, an attacker can gain unauthorized access to administrative credentials, sensitive telemetry, or configuration data being transmitted through the gateway. Given the nature of SCG as a central connectivity point for enterprise infrastructure, the potential for lateral movement or deeper intelligence gathering is high. The scope of impact is limited to the transport layer security mechanisms employed by the appliance during remote communication sessions."
}