CVE-2026-79807

Executive Summary

CVE-2026-79807 is a missing integrity verification vulnerability in the Windows client software for ClearPass Policy Manager, the network access control (NAC) platform administered by Aruba (Hewlett Packard Enterprise). A malicious local user on a Windows endpoint running the affected client can abuse the absence of integrity validation to elevate their privileges and execute attacker-supplied code with elevated rights on that local system. The flaw carries a CVSS 3.1 base score of 7.8 (High), and no public proof-of-concept, exploit code, or vendor patch has been observed as of this writing.

Technical Analysis

ClearPass Policy Manager is a network access control product used to authenticate and authorize devices and users across wired, wireless, and VPN infrastructure. The product includes a Windows client component that is deployed to endpoints, typically to broker authentication, posture assessment, and role-based access decisions against the central Policy Manager appliance.

The vulnerability class here is insufficient integrity verification (CWE-345). Per the NVD description, the defect lies in the Windows client software and manifests as a missing validation step that would normally confirm the authenticity or integrity of data/code the client processes. Because that verification is absent, a user who already holds a low-privileged local foothold on the machine can influence or substitute the code/data that the Windows client subsequently handles in an elevated context.

The CVSS vector is instructive about the attack model:

• AV:L (Local) — the attacker must already execute code or operate a session on the target Windows host. This is not remotely triggerable over the network.
• AC:L (Low) — no special race conditions or complex preconditions are required beyond the missing check itself.
• PR:L (Low) — the attacker needs only ordinary user credentials, not administrative rights.
• UI:N (None) — no victim interaction is required at exploit time.
• S:U (Unchanged) — the impact is confined to the security scope of the vulnerable Windows client component.
• C:H / I:H / A:H — full loss of confidentiality, integrity, and availability is possible, consistent with arbitrary code execution in an elevated context.

The exact routine, component, or binary path within the Windows client that performs (or fails to perform) the integrity check is not disclosed in the available description. No CWE assignment was supplied by the CNA, and no affected version range, fixed version, or advisory technical detail is present in the provided data. Accordingly, the mechanism is characterized at the vulnerability-class level: a trust boundary between unprivileged local input and an elevated client operation exists without a corresponding validation gate.

Exploitation Scenarios

The attack chain is inferred from the vulnerability class (missing integrity verification in a Windows client) and the CVSS vector (local, low-privileged, no user interaction). No public PoC or exploit code exists, so no code-level sequence can be asserted.

1. Reconnaissance / target identification. The attacker requires a foothold on a Windows endpoint that has the ClearPass Policy Manager Windows client installed — common in enterprises using ClearPass for NAC enforcement. The attacker confirms the client's presence and identifies the elevated operation it performs (for example, a service, scheduled task, or privileged process the client invokes). No network-level reconnaissance against the Policy Manager appliance is required by the vector.

2. Triggering the verifier gap. Because the client does not verify the integrity of data or code it consumes in a privileged context, the low-privileged attacker places or manipulates the unverified artifact in a location the elevated process will read. The specific artifact, directory, or API is not disclosed in the available description and must not be assumed.

3. Payload / execution. At the vulnerability-class level, the attacker supplies their own code where the client expects legitimately signed or verified content, and the client executes it without the missing integrity check blocking it. The precise execution primitive (service load, inter-process call, or similar) cannot be stated from the provided data.

4. Post-exploitation impact. Successful exploit yields code execution with elevated privileges on the local system, matching the C:H/I:H/A:H subscores. From an elevated local context the attacker could disable security tooling, harvest credentials, pivot to the ClearPass Policy Manager appliance using stored service or client credentials, and use the NAC position to manipulate network admission policy.

Note: the CVSS PR:L rating and local-only vector mean this is a classic privilege-escalation primitive that is typically chained after initial access (for example, following phishing or a separate RCE), not a standalone network attack.

Impact Assessment

Successful exploitation grants a local, low-privileged user elevated code execution on the affected Windows host. In a NAC deployment, the Windows clients are frequently found on managed endpoints, administrative workstations, and IT jump hosts — systems that often hold trusted relationships to the ClearPass Policy Manager appliance and to authentication infrastructure.

Business impact factors:

• Confidentiality (High): elevated access enables credential and configuration theft, potentially exposing network access credentials and NAC secrets.
• Integrity (High): attacker-controlled code in an elevated context can alter system state, security controls, and client behavior.
• Availability (High): a local administrator can disrupt the host, and a compromised NAC client relationship could affect admission decisions for the broader environment.
• Blast radius: initially confined to the compromised endpoint (Scope: Unchanged), but enterprise deployments commonly distribute the client broadly, meaning many endpoints share the same vulnerable code. Lateral movement toward the Policy Manager appliance is a realistic escalation of impact.

No EPSS score is available (not yet scored by FIRST.org), no CISA KEV listing exists, and there is no observed exploit-in-the-wild evidence in the provided data. The absence of a patch (patch confidence 0/4) means exposure persists for every unmitigated deployment.

Detection Guidance

Sigma Rule

title: Potential ClearPass Windows Client Privilege Escalation via Missing Integrity Check (CVE-2026-79807)
id: 8b1f4c2e-7d3a-4f6b-9c21-5e0a7d9b3c11
status: experimental
description: Detects suspicious process creation and privilege-escalation behaviour associated with the ClearPass Policy Manager Windows client, where a low-privileged process spawns elevated content due to missing integrity verification. Tune directory and binary names to your environment.
references:
  - https://nvd.nist.gov/vuln/detail/CVE-2026-79807
author: Threat Intelligence Team
date: 2026/01/01
tags:
  - attack.privilege_escalation
  - attack.t1068
logsource:
  product: windows
  category: process_creation
detection:
  selection_client:
    ParentImage|endswith:
      - '\ClearPass*'
      - '\ClearPassAgent*'
  selection_suspicious_child:
    Image|endswith:
      - '\cmd.exe'
      - '\powershell.exe'
      - '\pwsh.exe'
      - '\rundll32.exe'
      - '\regsvr32.exe'
      - '\mshta.exe'
  condition: selection_client and selection_suspicious_child
falsepositives:
  - Legitimate maintenance scripts executed by the ClearPass client
  - Vendor update or diagnostic operations
level: high

YARA Rule

rule CVE_2026_79807_ClearPass_Client_Anomaly
{
    meta:
        description = "Heuristic detection of tampered or unsigned ClearPass Policy Manager Windows client artifacts that may indicate exploitation of missing integrity verification (CVE-2026-79807)"
        author = "Threat Intelligence Team"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-79807"
        date = "2026-01-01"
        severity = "high"

    strings:
        $client1 = "ClearPass" ascii wide nocase
        $client2 = "Policy Manager" ascii wide nocase
        $client3 = "ClearPassAgent" ascii wide nocase

    condition:
        (uint16(0) == 0x5A4D) and
        any of ($client*) and
        not for any of ($client*) : ( $ at 0 )
}

Suricata IDS Rule

alert tcp any any -> any any (msg:"CVE-2026-79807 - ClearPass Policy Manager Windows Client Privilege Escalation Artifact Transfer"; flow:established,to_client; content:"ClearPass"; nocase; content:"Policy Manager"; nocase; distance:0; within:512; threshold: type limit, track by_src, count 1, seconds 60; classtype:attempted-user; sid:202679807; rev:1; metadata:reference cve CVE-2026-79807;)

Note: this vulnerability is local in nature and produces no reliable network signature of its own; the rule above provides contextual coverage for artifact delivery and should be complemented with host-based telemetry.

Elastic Detection

process where event.type == "start" and
  process.parent.name : ("ClearPass*", "ClearPassAgent*") and
  process.name : ("cmd.exe", "powershell.exe", "pwsh.exe", "rundll32.exe", "regsvr32.exe", "mshta.exe") and
  process.args : ("*http*", "*-enc*", "*-e *", "*FromBase64*")

Splunk SPL Query

index=windows EventCode=4688
| where match(ParentProcessName, "(?i)ClearPass|ClearPassAgent")
| where match(NewProcessName, "(?i)cmd\.exe|powershell\.exe|pwsh\.exe|rundll32\.exe|regsvr32\.exe|mshta\.exe")
| stats count min(_time) as first_seen max(_time) as last_seen values(NewProcessName) as child_process by ComputerName, SubjectUserName, ParentProcessName
| where count >= 1
| sort - last_seen

Wazuh OSSEC Rule

<group name="windows,clearpass,privilege_escalation,">
  <rule id="100807" level="12">
    <if_sid>60000</if_sid>
    <field name="win.eventdata.parentImage">(?i)ClearPass|ClearPassAgent</field>
    <field name="win.eventdata.image">(?i)(cmd\.exe|powershell\.exe|pwsh\.exe|rundll32\.exe|regsvr32\.exe|mshta\.exe)$</field>
    <description>CVE-2026-79807: Suspicious elevated child process spawned by ClearPass Policy Manager Windows client</description>
    <mitre>
      <id>T1068</id>
    </mitre>
    <group>cve_2026_79807,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source). No vendor fix, workaround, or fixed version is available in the provided intelligence.

1. Immediate mitigations

   • Remove or disable the ClearPass Policy Manager Windows client on hosts where it is not strictly required; the attack vector is local and eliminating the component removes the exposure.
   • Enforce least privilege: ensure standard users cannot write to directories, services, or registry keys consumed by any elevated ClearPass client process.
   • Apply application allowlisting (WDAC/AppLocker) so only signed, expected binaries can execute in the client's process tree.
   • Deploy the Sigma, EQL, SPL, and Wazuh detections above and tune them to your ClearPass client naming so that abnormal elevated child processes are flagged.
   • Monitor vendor channels (HPE Aruba Networking security advisories) for an official fix and treat any client update as time-critical.

2. Patch / upgrade steps

   • No patched version exists yet. Subscribe to Aruba/HPE security bulletins for ClearPass Policy Manager and ClearPass client releases.
   • When a fix ships, upgrade the Windows client on all managed endpoints and verify the updated build performs the missing integrity verification.
   • Validate after upgrade by confirming only signed, expected artifacts are processed by elevated client operations.

3. Long-term hardening

   • Segment and monitor trust relationships between Windows clients and the ClearPass Policy Manager appliance; alert on unexpected authentication or API activity from endpoints.
   • Enforce credential hygiene for any service accounts or client credentials used by the ClearPass client, rotating them and scoping their rights.
   • Add integrity and signature verification requirements to internal software review standards, and audit other local privileged components in the NAC stack for the same class of flaw.
   • Favour architecture that minimizes the number of local privileged helpers that process unauthenticated or unverified input.

References

• NVD — CVE-2026-79807: https://nvd.nist.gov/vuln/detail/CVE-2026-79807
• MITRE ATT&CK T1068 — Exploitation for Privilege Escalation: https://attack.mitre.org/techniques/T1068/
• MITRE CWE-345 — Insufficient Verification of Data Authenticity: https://cwe.mitre.org/data/definitions/345.html
• HPE Aruba Networking Security Advisories (monitor for ClearPass Policy Manager bulletins): https://www.arubanetworks.com/support-services/security-bulletins/
• FIRST EPSS (no score available at time of writing): https://www.first.org/epss/

No threat actor campaigns, exploit-in-the-wild evidence, public PoC, or CISA KEV listing were identified in the provided data for this CVE.