CVE-2026-76779

Executive Summary

CVE-2026-76779 is a CWE-307 "Improper Restriction of Excessive Authentication Attempts" vulnerability affecting Dell Secure Connect Gateway (SCG) Policy Manager in versions prior to 5.34.00.16. An unauthenticated attacker with remote network access can exploit insufficient authentication-attempt throttling to conduct repeated credential-guessing against the affected service, potentially resulting in elevation of privileges, protection mechanism bypass, and unauthorized access. No public PoC, exploit code, or Nuclei template exists, and no patch evidence has been identified in any tracked source, leaving all deployments below 5.34.00.16 exposed until an official fix is published.

Technical Analysis

CVE-2026-76779 is classified under CWE-307, Improper Restriction of Excessive Authentication Attempts. This weakness class describes systems that fail to limit the frequency, volume, or rate of authentication attempts, thereby allowing an attacker to perform sustained credential guessing without lockout, exponential backoff, CAPTCHA, or other throttling controls. The affected component is Dell Secure Connect Gateway (SCG) Policy Manager, a remote-support and gateway management product that administers policy and connectivity for managed Dell environments.

Per the NVD description, the flaw resides in SCG Policy Manager versions prior to 5.34.00.16. The attack surface is the network-exposed authentication interface of Policy Manager. Because the CVSS vector specifies AV:N (network) with PR:N (no privileges required) and UI:N (no user interaction), the vulnerable authentication endpoint is reachable directly by an unauthenticated remote client. The AC:H (high attack complexity) rating indicates that successful exploitation is not deterministic — for example, it may require valid account enumeration, favorable lockout conditions, credential validity, or timing/environmental factors outside the attacker's full control — which is consistent with a brute-force / credential-guessing weakness where success depends on the quality of targeted credentials rather than an automatically repeatable exploit.

No specific function names, endpoints, parameters, or code paths are disclosed in the available NVD description or CNA title. Accordingly, this analysis deliberately describes the vulnerability at the class level: the authentication subsystem does not adequately restrict excessive attempts, enabling repeated authentication requests. The confidentiality and integrity subscores are both High (C:H/I:H) while availability is None (A:N), consistent with an attacker gaining authenticated access and the ability to modify policy/configuration data without degrading service availability. Scope is Unchanged (S:U), and the base score is 7.4 (High).

No public vulnerability research, exploit code, or PoC artifacts for this CVE were identified. The technical mechanism beyond the CWE-307 classification and the product/version range cannot be further specified from available data.

Exploitation Scenarios

No public PoC is available; the attack chain below is inferred from the vulnerability class (CWE-307) and the CVSS/attack-surface attributes supplied in the NVD data.

1. Reconnaissance / target identification: An attacker with network reachability to a Dell Secure Connect Gateway Policy Manager deployment identifies the service via its exposed management/authentication interface. Asset discovery can leverage internet-wide scan data (e.g., Shodan queries such as those in METADATA) and known Dell SCG product fingerprinted pages. The attacker confirms the version is below 5.34.00.16 where feasible.

2. Triggering the flaw class: The attacker sends repeated authentication requests to the Policy Manager login/authentication interface. Because the product reportedly fails to properly restrict excessive authentication attempts, the attacker is not reliably locked out, rate-limited, or otherwise blocked after repeated failures. This enables offline-style password guessing against valid accounts and/or username enumeration based on differential responses.

3. Payload / execution method: At the vulnerability-class level, exploitation consists of automated credential guessing (dictionary, credential-stuffing, or password-spraying) against the affected authentication interface, using remotely issued requests over the network. No specific endpoint, parameter, or request format is identified in the available data, so no request template is provided here. Weaponization may use standard brute-force tooling; the absence of throttling is the enabling factor rather than a memory-corruption or injection primitive.

4. Post-exploitation impact: Upon a successful guess, the attacker obtains authenticated access to Policy Manager, consistent with the NVD-stated outcomes — elevation of privileges, protection mechanism bypass, and unauthorized access. With High confidentiality and integrity impact, the attacker could read sensitive management/policy data and modify configuration or policy content. Availability impact is rated None, so service disruption is not an expected primary outcome. The AC:H rating implies exploitation success is contingent on attacker-chosen credentials matching valid accounts, making targeted, low-and-slow guessing against known usernames the most plausible approach.

Impact Assessment

Business impact: Successful exploitation yields unauthorized access to Dell Secure Connect Gateway Policy Manager with High confidentiality and High integrity impact per the CVSS vector. Because SCG operates in remote-support/management contexts, unauthorized access could expose sensitive infrastructure and policy data and permit unauthorized modification of policy and configuration. Scope is Unchanged, so the direct security authority is limited to the vulnerable component, though downstream management actions could have broader operational significance.

Affected systems: Dell Secure Connect Gateway (SCG) Policy Manager, versions prior to 5.34.00.16. Any deployment exposing the Policy Manager authentication interface to untrusted networks is at risk. The product/affected-version metadata in the supplied data did not enumerate explicit version lists beyond the "< 5.34.00.16" range.

Blast radius: Exploitation is network-accessible and requires no privileges or user interaction (AV:N/PR:N/UI:N), so exposure is driven chiefly by whether the authentication service is reachable. Attack complexity is High (AC:H), which reduces the likelihood of trivial mass exploitation but does not eliminate risk for targeted actors. Availability impact is None (A:N), so denial-of-service is not an expected consequence. CISA KEV status is NO, EPSS is not yet scored, and no public exploit or PoC has been observed — indicating no confirmed in-the-wild exploitation at the time of writing. Overall base score: 7.4 (High).

Detection Guidance

Sigma Rule

title: Excessive Failed Authentication Attempts Against Dell Secure Connect Gateway Policy Manager
id: 7f2c1a90-5b3e-4d21-9c88-3a6d0f76779a
status: experimental
description: Detects repeated failed authentication attempts consistent with CWE-307 exploitation (CVE-2026-76779) against Dell Secure Connect Gateway Policy Manager.
references:
  - https://nvd.nist.gov/vuln/detail/CVE-2026-76779
author: valtersit.com
date: 2026-01-01
logsource:
  category: authentication
  product: dell_scg
detection:
  selection_product:
    product|contains:
      - 'Secure Connect Gateway'
      - 'Policy Manager'
  selection_failure:
    event_outcome: 'failure'
    action: 'login'
  timeframe: 5m
  condition: selection_product and selection_failure | count() by source_ip > 20
falsepositives:
  - Legitimate users repeatedly mistyping credentials
  - Misconfigured automated integrations with stale credentials
level: high
tags:
  - attack.credential_access
  - attack.t1110
  - cve.2026.76779

YARA Rule

rule CVE_2026_76779_SCG_PolicyManager_Excessive_Auth_Attempts
{
    meta:
        description = "Detects references to Dell Secure Connect Gateway Policy Manager versions prior to 5.34.00.16 associated with CVE-2026-76779"
        author = "valtersit.com"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-76779"
        cve = "CVE-2026-76779"
        date = "2026-01-01"

    strings:
        $s1 = "Secure Connect Gateway" ascii wide nocase
        $s2 = "Policy Manager" ascii wide nocase
        $v1 = "5.34.00.16" ascii wide

    condition:
        uint16(0) == 0x5A4D and
        (($s1 or $s2) and $v1) or
        (2 of ($s1, $s2))
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-76779 Possible Excessive Authentication Attempts Against Dell Secure Connect Gateway Policy Manager"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"login"; nocase; threshold:type both, track by_src, count 20, seconds 300; classtype:attempted-user; reference:cve,2026-76779; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-76779; metadata:service http; sid:202676779; rev:1;)

Elastic Detection

sequence by source.ip with maxspan=5m
  [ authentication where event.outcome == "failure" and
      (user_agent.original : "*" or process.name : "*") ] with runs = 20

Splunk SPL Query

index=auth sourcetype=*
| search ("Secure Connect Gateway" OR "Policy Manager" OR scg)
| where action="login" AND outcome="failure"
| stats count AS failed_attempts, values(user) AS target_users, dc(user) AS distinct_users by src_ip
| where failed_attempts > 20
| sort - failed_attempts

Wazuh OSSEC Rule

<group name="dell_scg,cve-2026-76779,">
  <rule id="100779" level="10" frequency="20" timeframe="300">
    <if_matched_sid>5710</if_matched_sid>
    <same_source_ip />
    <description>CVE-2026-76779: Excessive failed authentication attempts possibly targeting Dell Secure Connect Gateway Policy Manager</description>
    <mitre>
      <id>T1110</id>
    </mitre>
    <group>authentication_failures,credential_access,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source). No vendor fix, workaround, or affected-version list was supplied in the available data.

1. Immediate mitigations:

• Do not expose the Dell Secure Connect Gateway Policy Manager authentication interface to untrusted networks. Restrict access to trusted management networks via firewall/ACL rules and segmentation.
• Place the management interface behind a VPN, bastion host, or zero-trust access gateway so that authentication endpoints are not directly reachable from the internet.
• Enforce account lockout, exponential backoff, CAPTCHA, and rate-limiting at an upstream reverse proxy, WAF, or identity-aware proxy if the appliance itself does not adequately throttle attempts (the vulnerable behavior identified by CWE-307).
• Enable MFA where the product and deployment support it, and audit for weak, default, or shared credentials.
• Monitor authentication logs for high-volume failed-login patterns from single source IPs (see Detection Guidance).

2. Patch / upgrade steps:

• No patch is currently available from tracked sources. Monitor Dell's official security advisory channel for Secure Connect Gateway and apply the fixed release as soon as a version at or above 5.34.00.16 (or a vendor-designated fixed build) is published.
• Treat 5.34.00.16 as the version boundary referenced by the NVD description ("versions prior to 5.34.00.16"); verify the actual remediated build against the forthcoming Dell advisory before assuming remediation.
• Maintain an inventory of SCG Policy Manager instances to rapidly identify and upgrade vulnerable deployments once a fix ships.

3. Long-term hardening:

• Establish a formal patch-management and vulnerability-monitoring process for remote-support/management appliances, which are high-value targets.
• Reduce the exposed attack surface of management tooling; apply least-privilege and network-segmentation principles.
• Harden authentication centrally: strong password policies, unique service credentials, MFA, and centralized lockout/throttling controls.
• Continuously monitor EPSS and CISA KEV for exploitability signals and update risk posture accordingly; no EPSS score or KEV listing currently exists for this CVE.

References

• NVD — CVE-2026-76779: https://nvd.nist.gov/vuln/detail/CVE-2026-76779
• Dell Secure Connect Gateway product/security advisory portal: https://www.dell.com/support/security (no CVE-specific advisory confirmed in available data)
• CWE-307 — Improper Restriction of Excessive Authentication Attempts: https://cwe.mitre.org/data/definitions/307.html
• MITRE ATT&CK T1110 — Brute Force: https://attack.mitre.org/techniques/T1110/
• CISA Known Exploited Vulnerabilities Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog (CVE-2026-76779 not listed as of this writing)

Threat actor campaigns / exploit-in-the-wild: No public PoC, exploit code, Nuclei template, EPSS score, or CISA KEV entry exists for CVE-2026-76779. No known threat actor campaign or in-the-wild exploitation has been identified in the available data.