CVE-2026-79643: Dell SCG 5.0 Authentication Bypass Vulnerability

CVE-2026-79643 Overview

CVE-2026-79643 affects Dell Secure Connect Gateway (SCG) 5.0 Appliance and Application versions. The vulnerability stems from a Use of Incorrect Operator flaw [CWE-480] in the affected components. An unauthenticated remote attacker can exploit this weakness over the network to gain unauthorized access to the appliance. Dell has published an advisory tracked as DSA-2026-382 and released fixed versions to address the issue.

Critical Impact

Unauthenticated remote attackers can obtain unauthorized access to Dell SCG 5.0 deployments, exposing gateway functions and any data traversing the connect gateway.

Affected Products

• Dell SCG 5.0 Appliance versions prior to 5.36.00.16
• Dell SCG 5.0 Application versions prior to 5.36.00.00
• Dell Secure Connect Gateway Virtual Edition (per DSA-2026-382)

Discovery Timeline

• 2026-09-07 - CVE-2026-79643 published to the National Vulnerability Database (NVD)
• 2026-09-08 - Last updated in NVD database

Technical Details for CVE-2026-79643

Vulnerability Analysis

CVE-2026-79643 is categorized as a Use of Incorrect Operator weakness [CWE-480]. This class of defect occurs when a developer uses an operator that does not match the intended logic, such as substituting an assignment operator for an equality comparison or using a bitwise operator where a logical operator is required. In security-sensitive code paths, this frequently produces a condition that always evaluates in the attacker's favor.

Dell describes the runtime effect as unauthorized access reachable by an unauthenticated remote attacker. The flaw resides in Dell Secure Connect Gateway 5.0, a gateway used to broker remote support and telemetry between Dell infrastructure and Dell backend systems. Exploitation does not require prior credentials, user interaction, or elevated privileges on the target appliance.

The Exploit Prediction Scoring System (EPSS) currently rates the probability of exploitation at 0.255%. No public proof-of-concept code is available at time of writing, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.

Root Cause

The root cause is an incorrect operator used within an authentication or access-control decision inside the SCG code base. When the operator evaluates unexpectedly, the enforcement check fails open, allowing an unauthenticated request to reach protected functionality. Dell has not published a code-level breakdown of the exact expression.

Attack Vector

The attack vector is network-based. An attacker with reachability to the SCG management or service interfaces can send crafted requests to trigger the flawed conditional. Successful exploitation results in unauthorized access to gateway functionality without authentication.

No verified exploit code is available. Refer to the Dell Secure Connect Gateway Update for vendor-provided technical context.

Detection Methods for CVE-2026-79643

Indicators of Compromise

• Unexpected authenticated sessions on SCG interfaces originating from unrecognized source IP addresses.
• New or modified configuration entries, users, or scheduled jobs on the SCG appliance without a corresponding change ticket.
• Outbound connections from the SCG appliance to hosts outside Dell's documented backend infrastructure.

Detection Strategies

• Compare installed SCG Appliance and Application versions against fixed builds 5.36.00.16 and 5.36.00.00 respectively.
• Baseline normal API and HTTP request patterns to the SCG management interface, then alert on anomalous unauthenticated requests to protected endpoints.
• Review web server and application logs for HTTP 200 or 302 responses on paths that should require authentication.

Monitoring Recommendations

• Forward SCG appliance logs to a centralized log platform for retention and correlation.
• Monitor administrative account creation, role changes, and credential updates on the appliance.
• Alert on configuration file changes and service restarts outside maintenance windows.

How to Mitigate CVE-2026-79643

Immediate Actions Required

• Upgrade Dell SCG 5.0 Appliance to version 5.36.00.16 or later.
• Upgrade Dell SCG 5.0 Application to version 5.36.00.00 or later.
• Restrict network reachability to SCG management interfaces using firewall rules or network segmentation until patching is complete.
• Rotate credentials and API tokens stored on or used by the SCG appliance after upgrading.

Patch Information

Dell has released fixed versions as part of security advisory DSA-2026-382. Administrators should follow the upgrade procedure documented in the Dell Secure Connect Gateway Update advisory. Verify the appliance and application versions after upgrade before restoring normal network exposure.

Workarounds

• Limit inbound access to the SCG appliance to trusted administrative subnets only.
• Place the appliance behind a reverse proxy or web application firewall that enforces authentication at the network edge.
• Disable or isolate the appliance if patching cannot be completed and exposure cannot be constrained.

# Example firewall restriction limiting SCG management access to a trusted subnet
iptables -A INPUT -p tcp --dport 443 -s 10.10.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP