CVE-2026-20789

Executive Summary

CVE-2026-20789 is an improper access control vulnerability (CWE-284) in Intel(R) PROSet/Wireless WiFi Software for Windows device drivers, classified by Intel under the "Ring 2: Device Drivers" component layer. A local, unauthenticated, unprivileged adversary can exploit it with low attack complexity and no user interaction to achieve local code execution, i.e., an escalation of privilege. The exact affected version range has not been disclosed and there is no evidence of an available patch, so enterprises relying on Intel PROSet/Wireless WiFi Software for Windows should treat any deployment as potentially affected and apply compensating controls pending an official fix.

Technical Analysis

The NVD description indicates that the root cause is improper access control within the device-driver component of Intel PROSet/Wireless WiFi Software for Windows. The product delivers kernel-mode drivers that provide wireless networking functionality, configuration, and management capabilities to the operating system and user-mode applications. Intel's description places the flaw in "Ring 2: Device Drivers," which is Intel's internal component classification for the driver layer delivered with this software stack.

From a vulnerability-class perspective, CWE-284 (Improper Access Control) means the driver fails to enforce the correct permissions, ownership, or state-based restrictions on a resource or operation exposed to callers. In the context of a Windows kernel-mode driver, this typically means that an interface (e.g., a device object or dispatch routine reachable from user mode) does not adequately validate the caller's privilege level, integrity level, or the security context of the request. Consequently, an unprivileged software process embedding in the current logged-on user session can submit crafted requests that the driver processes with elevated trust, ultimately resulting in execution of attacker-controlled code in a privileged context.

Several details in the description constrain the attack profile:

• Access vector (local): The attacker must already have the ability to execute code on the target host — for example, a malicious application, a piece of malware, or an attacker who has obtained unprivileged shell access. The vulnerability is not remotely exploitable over the network.
• Authentication (none): The attack requires only an "unauthenticated user," meaning the adversary does not need a privileged account. A standard, non-elevated Windows user or even a guest-level process context is sufficient.
• Complexity (low): No unusual conditions, race, or special preparation are required. The description explicitly states the attack requirements are "not present" without special internal knowledge, i.e., the attacker does not need to know undocumented internals to trigger the flaw.
• User interaction (none): The victim does not need to click a link, open a document, or perform any action. The attack is fully automated once the malicious process runs.
• Availability impact (high at first order): The vulnerable system's device-driver layer can be crashed, or resources can be consumed, causing high impact on availability of the wireless stack and potentially the wider system.

The subsequent system-level impacts (system confidentiality high, integrity low, availability low) indicate a typical local privilege escalation (LPE) chain: initial code execution inside the unprivileged context transitions to privileged code execution, after which the attacker can read sensitive data protected by higher-integrity processes, modify system state, and induce denial-of-service conditions. Insufficient technical detail is available regarding the exact driver interface, IOCTL codes, or specific function names, as neither the CNA title nor the NVD description discloses implementation-level identifiers. The analysis here is therefore grounded in the vulnerability class and the published impact statement.

Exploitation Scenarios

No public PoC is available, and no Nuclei template or exploit code is linked to this CVE. The attack chain below is inferred strictly from the vulnerability class (improper access control in a kernel-mode driver) and the parameters stated in the NVD description. Specific function names, file paths, and API endpoints are intentionally omitted because they are not disclosed in the provided data.

1. Reconnaissance / target identification: The adversary identifies a host running Intel PROSet/Wireless WiFi Software for Windows with an active Intel wireless adapter. This can be done by enumerating installed programs, inspecting running services, or checking loaded drivers from an unprivileged session. Since the exact vulnerable version range is unknown, any version of the software is a candidate until a patched build is published. The attacker may target enterprise fleets where this software is commonly pre-installed on laptops and mobile workstations.

2. Triggering the flaw: The attacker executes a benign-looking but malicious unprivileged process on the target. This process opens a handle to the exposed driver interface and issues a series of requests (at the vulnerability-class level, e.g., IOCTL-style calls or device-object method invocations) that the driver fails to gate with proper access-control checks. Because the vulnerability is described as low complexity and requiring no user interaction, a standard unprivileged process is sufficient; no UAC bypass, no special internal knowledge, and no user action are required.

3. Payload / execution method: The crafted requests cause the driver to perform an action on behalf of the caller without verifying the caller's privilege level. The result is that the attacker's code executes in the context of the driver — i.e., with kernel or elevated-privilege authority. At the class level, the payload can be any shellcode, DLL, or executable that the attacker intends to run with elevated privileges; the driver acts as the confused deputy that grants that elevation. No specific payload content can be asserted beyond this, as no exploit code has been published.

4. Post-exploitation impact: After successfully escalating privileges, the adversary gains the ability to read sensitive system data (subsequent confidentiality high), tamper with system or security components (integrity low), and degrade or deny system services (availability low). Typical post-exploitation goals include extracting credentials from LSASS or registry hives, disabling security tooling, creating persistent backdoors via services or scheduled tasks, and staging lateral movement to other hosts. The initial device-level impact — high availability — suggests the driver component itself can also be forced into an unstable state, causing crashes or blue-screens for the wireless subsystem.

Impact Assessment

• Business impact: Intel PROSet/Wireless WiFi Software is widely deployed on enterprise laptops, workstations, and some embedded or thin-client environments that use Intel wireless radios. Because the attack is local and requires no authentication, the primary threat is from malware already present on the endpoint or from malicious insider activity. In a shared or multi-user environment (e.g., kiosk, VDI with local pass-through, lab machines), an unprivileged user could compromise the entire host.
• Blast radius: Each exploitation event is host-scoped, but the software's widespread deployment means the vulnerable population is large. If the flaw can also be triggered from a sandboxed or low-integrity process, it becomes a valuable bypass primitive for web-delivered malware or browser drive-by chains (shellcode downloaded to disk and executed locally with low privileges, then escalated via this CVE).
• CVSS context: The CVSS vector is N/A in the available data; the description's qualitative factors (local access, low complexity, no user interaction, no authentication) are consistent with a high-severity local privilege escalation. The EPSS score of 0.00126 (2.6th percentile of exploited CVEs) indicates that, at the time of publication, mass exploitation in the wild is not observed and exploitation likelihood is comparatively low relative to the broader CVE population. The CVE is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
• Integrity considerations: The asymmetric impact profile (low system integrity but high system confidentiality after exploitation) suggests the attacker gains read-heavy access — e.g., memory/disk reads of protected data — rather than a stable kernel write primitive, although the high availability subscore on the vulnerable system warns that a stable write primitive may also permit deliberate system crashes.

Detection Guidance

Because this vulnerability is local, network-level signatures have limited fidelity. The detection rules below focus on the observable artifacts of exploitation and post-exploitation: anomalous driver loads, suspicious process activity referencing Intel PROSet/Wireless WiFi components, and privilege-side-effect events (e.g., new privileged processes spawned from unprivileged parents). Tune rules to your baseline and validate against legitimate wireless drivers before enabling in production.

Sigma Rule

title: Suspicious Intel PROSet Wireless WiFi Driver Load
id: 5f7d9c2e-4d1a-4b2c-9e3f-8a1b2c3d4e5f
status: experimental
description: Detects driver load events associated with Intel PROSet/Wireless WiFi software, which may indicate exploitation of CVE-2026-20789 (improper access control, local privilege escalation).
author: ValtersIT SOC
logsource:
  product: windows
  category: driver_load
detection:
  selection:
    ImageLoaded|contains:
      - 'Intel'
      - 'PROSet'
      - 'Wireless'
  filter_known_good:
    ImageLoaded|endswith:
      - 'Netwtw*.sys'          # known-good Intel WiFi driver naming pattern (adjust to environment)
  condition: selection and not filter_known_good
falsepositives:
  - Legitimate startup of Intel wireless driver during system boot
  - Lenovo/Dell/HP system management utilities loading Intel components
level: medium

YARA Rule

rule CVE_2026_20789_Intel_PROSet_Artifacts
{
    meta:
        author      = "ValtersIT SOC"
        description = "Detects binaries or memory artifacts referencing CVE-2026-20789 and Intel PROSet/Wireless WiFi driver strings"
        reference   = "https://nvd.nist.gov/vuln/detail/CVE-2026-20789"
        date        = "2026-01-01"
        cve         = "CVE-2026-20789"

    strings:
        $cve  = "CVE-2026-20789" ascii wide
        $p1   = "Intel(R) PROSet/Wireless WiFi Software" ascii wide
        $p2   = "PROSet/Wireless WiFi" ascii wide
        $p3   = "Ring 2: Device Drivers" ascii wide
        $p4   = "Improper access control" ascii wide

    condition:
        uint16(0) == 0x5A4D and
        ( $cve or ($p1 or $p2) or ($p3 and $p4) )
}

Suricata IDS Rule

# CVE-2026-20789 is a local privilege escalation; this rule targets exploit
# delivery and command-and-control chatter referencing the CVE or the affected product.
# It is a low-fidelity indicator — correlate with host telemetry.

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET POLICIES Possible CVE-2026-20789 Intel PROSet WiFi exploit payload download"; flow:established,to_server; http.uri; content:"CVE-2026-20789"; nocase; http.user_agent; content:"proset"; nocase; classtype:attempted-admin; sid:2026078901; rev:1; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-20789;)

alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET INFO CVE-2026-20789 reference in inbound HTTP body"; flow:established,to_client; http.request; content:"CVE-2026-20789"; nocase; classtype:info; sid:2026078902; rev:1;)

Elastic Detection

// EQL: Detect a process spawning or loading components tied to Intel PROSet/Wireless
// WiFi, followed by an anomalous privilege session or new process creation,
// which may indicate post-exploitation activity after CVE-2026-20789.

sequence by host.id with maxspan=5m
  [ process where event.type == "start" and
      (process.name : "*proset*" or process.executable : "*Intel*Wireless*") ]
  [ process where event.type == "start" and
      process.Ext.relative_file_name_create : "*" and
      not process.parent.name : ("services.exe", "wininit.exe") ]

Splunk SPL Query

index=windows source="XmlWinEventLog:Microsoft-Windows-Sysmon/Operational"
| search EventCode=6
| search Image="*Intel*" AND (Image="*PROSet*" OR Image="*Wireless*")
| stats count earliest(_time) latest(_time) by host, Image, Signature, Hashes
| where count > 1
| sort - earliest

Wazuh OSSEC Rule

<rule id="100207" level="10">
  <if_sid>92000</if_sid>
  <groups>sysmon,</groups>
  <field name="system.eventID">^6$</field>
  <field name="win.event_data.Image">Intel</field>
  <field name="win.event_data.Image">PROSet</field>
  <description>CVE-2026-20789: Suspicious Intel PROSet/Wireless WiFi driver load detected (potential local privilege escalation)</description>
  <mitre>
    <id>T1068</id>
  </mitre>
  <options>no_full_log</options>
</rule>

Mitigation & Patch Guidance

Patch confidence is 0/4 (UNPATCHED) — no patch evidence from any tracked source exists. The vendor fix field is N/A, no workarounds are published, and no affected version list is available. Organizations should therefore treat all installations of Intel PROSet/Wireless WiFi Software for Windows as potentially vulnerable.

1. Immediate mitigations (before a patch exists):

   • Restrict local and interactive access to systems running the software. Enforce the principle of least privilege so unprivileged users cannot run arbitrary binaries on sensitive endpoints.
   • Deploy application control/allow-listing (e.g., WDAC, AppLocker) to block unsigned or untrusted executables, reducing the chance that a malicious unprivileged process can reach the driver interface.
   • If wireless functionality is not required on specific assets (e.g., desktop workstations with wired connections), disable or remove the Intel PROSet/Wireless WiFi software and the associated adapter to eliminate the attack surface.
   • Increase monitoring of endpoints running this software; enable Sysmon driver-load (Event ID 6) and Windows System event 7045 logging, and feed the detection rules in this report into your SIEM.
   • Verify no exploitation has already occurred by triaging systems for unusual driver loads, new services, or privilege-side-effect events.

2. Patch / upgrade steps:

   • Monitor the Intel Security Center advisory page and the NVD entry for CVE-2026-20789 for a vendor advisory, patched version, or mitigation guidance.
   • When a patched version is released, deploy it through standard fleet-management channels (Windows Update, WSUS, SCCM, or Intel Driver & Support Assistant). Validate the patched driver version against the affected-version range once Intel discloses it.
   • Until the vendor discloses the affected versions, treat all currently shipped versions as vulnerable and prioritize patching based on asset criticality.

3. Long-term hardening:

   • Maintain a formal vulnerability-management cadence that includes driver/BIOS updates from the hardware vendor, not just OS patches.
   • Harden endpoints with Credential Guard, HVCI (Memory Integrity), and virtualization-based security to blunt the impact of kernel-level LPEs.
   • Segment high-value servers from endpoint fleets so a single-host LPE cannot easily jump to sensitive internal systems.
   • Monitor EPSS and CISA KEV feeds for changes in CVE-2026-20789 exploitation status; if the CVE is later added to KEV, treat exploitation as confirmed in the wild and escalate response priority.

References

1. NVD Entry — CVE-2026-20789: https://nvd.nist.gov/vuln/detail/CVE-2026-20789
2. MITRE CVE Record — CVE-2026-20789: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-20789
3. Intel Security Center (for pending vendor advisory): https://www.intel.com/content/www/us/en/security-center/default.html
4. FIRST EPSS (score data for CVE-2026-20789): https://www.first.org/epss/
5. CISA Known Exploited Vulnerabilities Catalog (CVE-2026-20789 not currently listed): https://www.cisa.gov/known-exploited-vulnerabilities-catalog

No known threat-actor campaigns, exploit-in-the-wild evidence, or public proof-of-concept code has been identified for CVE-2026-20789 as of this report. The lack of CISA KEV listing and low EPSS percentile indicate that active exploitation has not been widely observed; however, the absence of a patch and the low exploitation barrier (local, low complexity, no interaction) warrant proactive defensive measures.