CVE-2026-79802

Executive Summary

CVE-2026-79802 is a command injection vulnerability (CWE-78) in the client software component of ClearPass Policy Manager. An attacker able to supply crafted input to the affected software can execute arbitrary commands with elevated privileges on the affected host. With a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H), the flaw is network-reachable and requires user interaction, but grants full confidentiality, integrity, and availability impact to the compromised endpoint.

Technical Analysis

ClearPass Policy Manager is a network access control (NAC) platform used for authentication, authorization, device profiling, and posture assessment of endpoints joining enterprise networks. The NVD entry states that the vulnerability resides in the "client software" of ClearPass Policy Manager, not in the server-side policy engine itself.

The vulnerability class is operating system command injection. Command injection occurs when an application constructs an operating system command using external input without proper sanitization or parameterization — for example, passing untrusted data into a shell invocation such as system(), exec(), popen(), or equivalent runtime primitives. Because shell metacharacters (;, |, &&, `, $()) are interpreted by the command interpreter, injected data is executed as part of the command line.

Two properties of the CVSS vector shape the analysis:

• AV:N (Network) — the crafted input can be supplied remotely across a network boundary, meaning the vulnerable client component processes input from a network-reachable channel rather than only from a local, trusted source.

• UI:R (User Interaction Required) — successful exploitation depends on a user (or the client process acting on a user's behalf) triggering the processing of the crafted input. This distinguishes the flaw from a fully unauthenticated, zero-interaction RCE and implies a delivery step such as a crafted message, file, or client-triggered operation.

• PR:N / S:U / C:H / I:H / A:H — no privileges are required of the attacker, the impact is scoped to the vulnerable component and the host it runs on, and the resulting command execution achieves complete loss of confidentiality, integrity, and availability on that host.

The critical escalation factor is stated directly in the description: commands execute "with elevated privileges." If the ClearPass client software runs as a privileged service or elevated user context, injected commands inherit those rights, enabling full host compromise rather than limited user-level execution.

The exact injection point, the parameter or field that accepts the crafted input, the shell primitive used, the client software component name, and the affected product version are not disclosed in the available description. No function names, endpoints, file paths, or parameters can be confirmed from the source data, and none are asserted here.

Exploitation Scenarios

No public proof-of-concept exists for CVE-2026-79802, and no Nuclei template or exploit code is available. The attack chain below is inferred strictly from the vulnerability class (command injection), the CVSS vector, and the NVD description. It does not assert implementation details that are not present in the source data.

1. Reconnaissance / target identification. An attacker identifies hosts running the ClearPass Policy Manager client software. Because the vector is AV:N, the attacker must be positioned to deliver input that the client consumes over a network-reachable channel. Discovery would focus on network-visible ClearPass client endpoints and, where applicable, the certificate and HTTP response characteristics of the product.

2. Trigger of the flaw class. The attacker supplies crafted input to the affected client software. The UI:R component indicates that exploitation requires a user-driven or client-side trigger: the client must process the malicious input for the injection to occur. At the vulnerability-class level, the crafted input contains shell metacharacters that are passed into a command interpreter without sanitization, causing an unintended command to be appended to or substituted within an intended command.

3. Payload / execution method. Because commands are executed with elevated privileges, the attacker's payload runs in an elevated context on the affected host. The attacker does not need to supply credentials (PR:N); they need only cause the vulnerable code path to process the malicious input. Any arbitrary command supported by the host operating system could be invoked in principle — command injection permits an attacker to run the interpreter's full command language.

4. Post-exploitation impact. With elevated command execution, the attacker achieves complete compromise of the affected host: reading sensitive data (ClearPass deployments hold authentication and policy data), modifying system state, installing persistence, and pivoting further into the network. Per CVSS, confidentiality, integrity, and availability impacts are all rated High on the affected host.

Because exploitation requires interaction and the vulnerable component is client software, the realistic threat model is a targeted attack against operators or administrators who use the ClearPass client — for example, via social engineering or a compromised upstream input source — rather than a self-propagating, unauthenticated mass exploit.

Impact Assessment

CVE-2026-79802 carries a CVSS v3.1 base score of 8.8 (High), vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

• Attack Vector (Network): exploitable across a network boundary; not confined to local or adjacent access.
• Attack Complexity (Low): no specialized conditions, race windows, or unusual preconditions are required beyond delivering the crafted input.
• Privileges Required (None): the attacker needs no prior account or authorization.
• User Interaction (Required): a user or client-side action must occur for the payload to be processed — the single mitigating factor in the vector.
• Scope (Unchanged): impact is contained to the vulnerable component and the host it runs on, rather than crossing an authorization boundary.
• Confidentiality / Integrity / Availability (High / High / High): successful exploitation yields total loss across all three security objectives on the affected host.

Business impact. ClearPass Policy Manager is central to enterprise network access control. Compromise of a client host that manages or interacts with ClearPass can expose authentication data and policy configuration, allow tampering with access decisions, and provide a foothold for lateral movement. Because execution is elevated, an affected endpoint should be treated as fully compromised.

Blast radius. The scope is limited to hosts running the affected client software (S:U). However, the strategic value of those hosts — particularly administrator and operator workstations — means a single successful compromise can have outsized network-wide consequences.

Exploitability context. EPSS has not yet scored this CVE, there is no CISA KEV listing, no public PoC, and no Nuclei template. Patch confidence is 0/4: no patch evidence exists from any tracked source, and no affected version range has been published. This combination — high severity, unpatched status, but no observed exploitation — argues for prioritized, proactive hardening rather than emergency response.

Detection Guidance

Sigma Rule

title: Command Injection Exploitation Attempt - ClearPass Policy Manager Client
id: 5f2c9a41-8b7e-4d13-9c2a-7e6f1d0b3a55
status: experimental
description: Detects suspicious process creation consistent with command injection via the ClearPass Policy Manager client software (CVE-2026-79802). Watches for shell interpreters spawned by client processes with shell metacharacter payloads in the command line.
references:
  - https://nvd.nist.gov/vuln/detail/CVE-2026-79802
author: valtersit.com
date: 2026/01/01
tags:
  - attack.execution
  - attack.t1203
  - attack.t1059.004
logsource:
  category: process_creation
  product: windows
detection:
  selection_parent:
    ParentImage|endswith:
      - '\ClearPassClient.exe'
      - '\ClearPass.exe'
  selection_shell:
    Image|endswith:
      - '\cmd.exe'
      - '\powershell.exe'
      - '\pwsh.exe'
      - '\bash'
      - '\sh'
  selection_meta:
    CommandLine|contains:
      - ';'
      - '&&'
      - '||'
      - '|'
      - '`'
      - '$('
      - '%COMSPEC%'
  condition: selection_parent and selection_shell and selection_meta
falsepositives:
  - Legitimate administrative scripts invoked by the client (rare)
level: high

YARA Rule

rule CVE_2026_79802_ClearPass_CommandInjection
{
    meta:
        description = "Detects command injection payload artifacts targeting ClearPass Policy Manager client software (CVE-2026-79802)"
        author = "valtersit.com"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-79802"
        date = "2026-01-01"
        severity = "high"

    strings:
        $shell1 = "cmd.exe" nocase
        $shell2 = "powershell" nocase
        $shell3 = "/bin/sh" nocase
        $shell4 = "/bin/bash" nocase

        $meta1 = ";" ascii
        $meta2 = "&&" ascii
        $meta3 = "||" ascii
        $meta4 = "$(" ascii
        $meta5 = "`" ascii
        $cpr1 = "ClearPass" nocase ascii wide

    condition:
        uint16(0) == 0x5A4D and
        $cpr1 and
        (any of ($shell*)) and
        (2 of ($meta*))
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-79802 ClearPass Client Command Injection Attempt - Shell Metacharacters"; flow:established,to_server; content:"ClearPass"; http_header; nocase; pcre:"/(;|\||&&|\$\(|`)\s*(cmd|powershell|sh|bash|wget|curl)/i"; classtype:attempted-admin; reference:cve,2026-79802; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-79802; sid:202679802; rev:1;)

Elastic Detection

process where event.type == "start" and
process.parent.name in ("ClearPassClient.exe", "ClearPass.exe") and
process.name in ("cmd.exe", "powershell.exe", "pwsh.exe", "bash", "sh") and
(process.command_line like~ "*;*" or
 process.command_line like~ "*&&*" or
 process.command_line like~ "*||*" or
 process.command_line like~ "*$(*" or
 process.command_line like~ "*`*")

Splunk SPL Query

index=endpoint (source="XmlWinEventLog:Microsoft-Windows-Sysmon/Operational" OR source="WinEventLog:Security")
EventCode=1
| rex field=ParentImage "\\\\(?<parent_proc>[^\\\\]+)$"
| rex field=Image "\\\\(?<child_proc>[^\\\\]+)$"
| where (parent_proc IN ("ClearPassClient.exe","ClearPass.exe"))
    AND (child_proc IN ("cmd.exe","powershell.exe","pwsh.exe","bash","sh"))
    AND (match(CommandLine, "[;&|`]|\$\("))
| table _time, host, User, parent_proc, child_proc, CommandLine
| sort - _time

Wazuh OSSEC Rule

<group name="windows,sysmon,cve_2026_79802,">
  <rule id="100802" level="12">
    <if_sid>61603</if_sid>
    <field name="win.eventdata.parentImage">ClearPass(Client)?\.exe</field>
    <field name="win.eventdata.image">\\(cmd|powershell|pwsh|bash|sh)\.exe</field>
    <regex field="win.eventdata.commandLine">[;&|`]|\$\(</regex>
    <description>CVE-2026-79802: Possible command injection via ClearPass Policy Manager client - shell spawned with metacharacter payload</description>
    <mitre>
      <id>T1203</id>
      <id>T1059</id>
    </mitre>
    <group>attack.execution,attack.t1203,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED). No patch, vendor fix, or affected-version data is available from any tracked source. No vendor advisory or affected version range has been published.

1) Immediate mitigations.

• Restrict network exposure of the ClearPass client so only trusted sources can supply input to the affected component.
• Limit privilege of the ClearPass client software where operationally feasible; reducing the client's execution context lowers the impact of injected commands.
• Apply application allowlisting to block unexpected shell interpreter execution (cmd.exe, powershell.exe, bash, sh) spawned by ClearPass client processes.
• Enforce least privilege for operators using the ClearPass client and segment those hosts from sensitive network segments.
• Because user interaction is required, reinforce phishing and social-engineering awareness for teams that operate ClearPass client software.

2) Patch/upgrade steps.

• No patch is currently available from tracked sources. Monitor the vendor (Aruba / HPE) security advisory portal and the NVD entry for CVE-2026-79802 for an updated record.
• Establish a watch on the official advisory channel and subscribe to vendor security notifications so the patch can be applied immediately on release.
• Before any future update, verify the integrity and provenance of the update package through the vendor's official distribution channel.

3) Long-term hardening.

• Treat ClearPass client workstations as high-value assets: harden them, restrict local administrative rights, and monitor them aggressively.
• Deploy input-validation-aware endpoint detection (see Detection Guidance) and enable detailed process-creation auditing across all ClearPass client hosts.
• Segment the network access control management plane from general user networks.
• Institute a vulnerability-management workflow that flags unpatched, high-CVSS, high-value-host findings for compensating control review.

References

• NVD — CVE-2026-79802: https://nvd.nist.gov/vuln/detail/CVE-2026-79802
• MITRE ATT&CK — T1203 Exploitation for Client Execution: https://attack.mitre.org/techniques/T1203/
• MITRE CWE-78 — Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection'): https://cwe.mitre.org/data/definitions/78.html
• FIRST EPSS (not yet scored for CVE-2026-79802): https://api.first.org/data/v1/epss?cve=CVE-2026-79802
• CISA Known Exploited Vulnerabilities Catalog (CVE-2026-79802 not listed): https://www.cisa.gov/known-exploited-vulnerabilities-catalog

No threat actor campaigns, exploit-in-the-wild evidence, public PoC, or Nuclei template are associated with CVE-2026-79802 in the available data.