CVE-2026-78022

Executive Summary

CVE-2026-78022 is a "Failing Open" (Not Failing Securely) vulnerability, CWE-636, affecting Dell Secure Connect Gateway (SCG) Policy Manager versions prior to 5.34.00.16. A low-privileged, remotely authenticated attacker can exploit the flaw to bypass a protection mechanism, granting unauthorized access to resources or policy state that should remain restricted. With a CVSS base score of 6.8 (AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N), impact is scored as high for confidentiality and integrity, but no public PoC, exploit code, or Nuclei template currently exists, and the CVE has not been added to CISA KEV.

Technical Analysis

The vulnerability class is CWE-636, "Not Failing Securely ('Failing Open')." This weakness occurs when a security control, upon encountering an error condition, an unexpected input, or a degraded operational state, defaults to an allowed or permissive state rather than a denied or restricted state. In security-critical logic — authentication gates, authorization checks, policy validation routines — the intended failure mode must be to close access; a "fail open" design instead leaves the control in a state that permits the operation to proceed.

The affected product is Dell Secure Connect Gateway (SCG) Policy Manager, a component used in Dell infrastructure environments to manage connectivity and policy between managed Dell systems and Dell support/backend services. Policy Manager governs the rules and configuration that mediate gateway connectivity, which is a high-value control plane: it determines what endpoints, telemetry, and support channels a managed fleet may reach. A protection-mechanism bypass in this layer can therefore affect the integrity of the entire gateway policy model, not just a single host.

Because the NVD description provides only the vulnerability class and impact (protection mechanism bypass) and does not enumerate specific functions, parameters, endpoints, or files, no code-level mechanism can be stated with certainty. What can be stated from the data: the flaw is remotely triggerable (AV:N), requires the attacker to already hold low privileges (PR:L), requires some degree of specialized conditions or timing to exploit reliably (AC:H), and requires no user interaction (UI:N). The organization is the security authority (S:U), so impact is contained to SCG Policy Manager and its trust boundary rather than assumed to escalate automatically across scopes.

The "Failing Open" designation implies a conditional path inside a validation or enforcement routine where a non-success result from a check is treated as an authorization grant. Without vendor code disclosure, the precise trigger (malformed input, an error state, an unexpected condition in a policy evaluation path, or a resource-unavailable condition) cannot be confirmed. Analysts should treat the exact trigger as unknown and rely on behavioral detection of anomalous policy-management activity.

Exploitation Scenarios

The following attack chain is inferred from the vulnerability class (CWE-636) and the CVSS metrics. No public PoC is available; no specific endpoints, functions, or parameters are asserted, because the source description does not disclose them.

1. Reconnaissance / target identification. The attacker identifies a reachable Dell Secure Connect Gateway (SCG) Policy Manager instance running a version prior to 5.34.00.16. Because the attack vector is network-based (AV:N), the Policy Manager management interface is the primary target. Shodan or internal asset inventory can be used to locate exposed instances, and version banners or product fingerprints confirm the vulnerable range.

2. Triggering the flaw class. The attacker needs low-privileged authenticated access (PR:L). Using a valid but limited account, the attacker interacts with the Policy Manager in a way that drives a security control into an error or degraded state. In a "failing open" weakness, the control's failure path resolves to "permit" instead of "deny." The exact malformed input or degraded condition is not disclosed by the available data and must be treated as unknown; exploitation conditions are non-trivial (AC:H), consistent with a state- or sequence-dependent trigger.

3. Payload / execution method at the class level. There is no memory-corruption or code-execution payload implied by CWE-636. The "payload" is the set of requests that steer the control into its insecure failure branch, after which the attacker performs an operation the protection mechanism was meant to block. Because UI is not required (UI:N), the trigger is server-side and does not depend on tricking an operator.

4. Post-exploitation impact. A successful bypass yields a protection-mechanism bypass with high confidentiality and integrity impact. The attacker can read and modify policy or configuration state normally reserved to higher-privileged roles — for example, altering gateway policy, weakening enforced restrictions, or accessing data gated by the bypassed control. Availability is scored as None (A:N), so the expected outcome is unauthorized access and modification, not service disruption.

Impact Assessment

Successful exploitation produces a protection-mechanism bypass with High Confidentiality and High Integrity impact (C:H/I:H), while availability impact is None (A:N). The scope is Unchanged (S:U), meaning the bypass is expected to affect SCG Policy Manager and its security authority rather than propagating to other independently scoped components. The attack requires low privileges (PR:L) and high attack complexity (AC:H), which lowers the likelihood of trivial, fully automated mass exploitation, consistent with the base score of 6.8 (Medium).

Business impact centers on the integrity of the gateway policy control plane. Because SCG Policy Manager mediates connectivity and policy for managed Dell infrastructure, a bypass can allow a low-privileged actor to weaken or circumvent intended restrictions on the gateway, potentially exposing management channels or permitting unauthorized configuration changes. The blast radius includes any environment where an attacker can obtain a low-privileged account and reach the Policy Manager interface; Internet-exposed or broadly reachable management instances represent the greatest risk. There is currently no evidence of active exploitation, KEV listing, or public exploit code, so the immediate threat is elevated-risk exposure rather than confirmed in-the-wild campaign use.

Detection Guidance

Sigma Rule

title: Dell SCG Policy Manager Fail-Open Protection Bypass Attempt
id: 6f3a9c22-7802-4d1a-9b7e-0c1e5a7b2201
status: experimental
description: Detects anomalous or repeated policy-management requests consistent with attempts to bypass protection controls (CWE-636) on Dell Secure Connect Gateway Policy Manager.
references:
  - https://nvd.nist.gov/vuln/detail/CVE-2026-78022
author: valtersit.com
date: 2026-01-01
logsource:
  category: webserver
  product: dell
  service: scg_policy_manager
detection:
  selection_paths:
    - cs-uri-stem|contains:
        - '/policy'
        - '/gateway'
        - '/config'
  selection_status:
    sc-status:
      - 200
      - 302
  selection_anomaly:
    - cs-uri-query|contains: 'admin'
    - cs-uri-query|contains: 'role'
    - cs-uri-query|contains: 'bypass'
  condition: selection_paths and selection_status and selection_anomaly
fields:
  - c-ip
  - cs-username
  - cs-uri-stem
  - sc-status
falsepositives:
  - Legitimate administrative policy changes by authorized administrators
level: medium
tags:
  - attack.t1190
  - cve.2026.78022

YARA Rule

rule CVE_2026_78022_SCG_PolicyManager_FailOpen
{
    meta:
        author = "valtersit.com"
        description = "Detects references to Dell Secure Connect Gateway Policy Manager vulnerable version range associated with CVE-2026-78022 (CWE-636 fail-open)"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-78022"
        date = "2026-01-01"
        cve = "CVE-2026-78022"
    strings:
        $prod1 = "Secure Connect Gateway"
        $prod2 = "SCG Policy Manager"
        $ver1 = "5.34.00.16"
        $hexver = { 35 2E 33 34 2E 30 30 2E 31 36 }
    condition:
        (uint16(0) == 0x5A4D or uint32(0) == 0x464C457F or true) and
        (any of ($prod1, $prod2)) and $ver1
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-78022 Dell SCG Policy Manager Fail-Open Protection Bypass Attempt"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"policy"; nocase; http.uri; content:"bypass"; nocase; classtype:attempted-admin; reference:cve,2026-78022; metadata:affected_product Dell_SCG_Policy_Manager, attack_target Server, created_at 2026_01_01, cve CVE_2026_78022; sid:202678022; rev:1;)

Elastic Detection

sequence by source.ip with maxspan=5m
  [ network where network.protocol == "http" and http.request.method == "GET" and
      url.path : ("*policy*", "*gateway*", "*config*") and
      http.response.status_code in (200, 302) ]
  [ network where network.protocol == "http" and
      url.query : ("*bypass*", "*role*", "*admin*") and
      http.response.status_code in (200, 302) ]

Splunk SPL Query

index=web OR index=proxy sourcetype=access_combined
| search (uri_path="*policy*" OR uri_path="*gateway*" OR uri_path="*config*")
| search (status=200 OR status=302)
| eval suspicious=if(match(uri_query, "(?i)(bypass|role|admin|privilege)"), 1, 0)
| where suspicious=1
| stats count values(uri_path) as paths values(uri_query) as queries by src_ip user
| where count > 5
| sort - count

Wazuh OSSEC Rule

<group name="dell,scg_policy_manager,web,">
  <rule id="202678" level="10">
    <decoded_as>web-accesslog</decoded_as>
    <match>policy|gateway|config</match>
    <regex>(bypass|role=|admin|privilege)</regex>
    <description>CVE-2026-78022: Possible Dell SCG Policy Manager fail-open protection bypass attempt detected.</description>
    <mitre>
      <id>T1190</id>
    </mitre>
    <group>cve_2026_78022,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source). The vendor advisory states that versions prior to 5.34.00.16 are affected and that upgrading addresses the flaw; however, no patch artifact, commit, or advisory confirmation has been independently verified from the tracked sources provided.

1. Immediate mitigations:

• Restrict network access to SCG Policy Manager management interfaces using firewall rules, VPN, or zero-trust access proxies; do not expose the interface to untrusted networks.
• Enforce least privilege and tightly scope low-privileged accounts, since exploitation requires an authenticated low-privileged user (PR:L).
• Audit and monitor policy-management activity for unauthorized or anomalous configuration changes; alert on unexpected privilege or policy modifications.
• Review logs for signs of a fail-open condition — operations succeeding where a control should have denied access.

2. Patch / upgrade steps:

• Upgrade Dell Secure Connect Gateway Policy Manager to version 5.34.00.16 or later. Confirm the exact version requirement against the official Dell advisory before and after the upgrade.
• Verify the successful upgrade via version enumeration and retain evidence for compliance.
• Monitor Dell's security advisory channel for updated guidance, as this CVE is currently unpatched in tracked sources.

3. Long-term hardening:

• Adopt a security architecture in which controls default to deny on error (fail-closed) and validate this property in code review and security testing.
• Integrate SBOM and version tracking for Dell Secure Connect Gateway components to detect vulnerable versions proactively.
• Include fail-open (CWE-636) conditions in threat modeling, secure design reviews, and regression tests for authentication and authorization components.
• Segment gateway and management infrastructure to limit blast radius if a protection control is bypassed.

References

• NVD — CVE-2026-78022: https://nvd.nist.gov/vuln/detail/CVE-2026-78022
• Dell Security Advisories (Secure Connect Gateway): https://www.dell.com/support/security
• MITRE CWE-636 — Not Failing Securely ('Failing Open'): https://cwe.mitre.org/data/definitions/636.html
• MITRE ATT&CK T1190 — Exploit Public-Facing Application: https://attack.mitre.org/techniques/T1190/
• CISA Known Exploited Vulnerabilities Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog (CVE-2026-78022 not listed as of this report; no threat actor campaigns or exploit-in-the-wild evidence currently available)