CVE-2026-20776

Executive Summary

CVE-2026-20776 is an unpatched denial-of-service (DoS) vulnerability in Intel(R) PROSet/Wireless WiFi Software, specifically within the Ring 2 device drivers. An unauthenticated network adversary located on an adjacent wireless network can trigger the flaw with low attack complexity and no user interaction, crashing the target system's WiFi stack and rendering the host unavailable. The official CVSS score and vector are N/A; however, the NVD description indicates a high availability impact with no confidentiality or integrity impact. As of this report, no vendor patch, affected version range, or public exploit evidence has been released, and the CVE is not listed in CISA's Known Exploited Vulnerabilities catalog.

Technical Analysis

Vulnerability class. The root cause maps to CWE-754 — Improper Check for Unusual or Exceptional Conditions. The Intel PROSet/Wireless WiFi driver fails to properly validate or handle an unusual/exceptional condition that arises during packet processing or wireless state transitions. In driver-level code, missing or incomplete condition checks typically allow malformed input or an unexpected protocol state to reach a code path that lacks the appropriate error handling, resulting in an uncontrolled fault (e.g., kernel bugcheck, driver hang, or system restart) rather than a graceful rejection of the input.

Fault location and privilege context. The vulnerability resides in Ring 2 (device drivers loaded within the Windows kernel context). This is significant: any fault triggered inside a kernel-mode driver can escalate to a full system crash (blue screen / bugcheck), which is consistent with the "high" availability impact stated in the NVD description and the absence of confidentiality/integrity impact. The description explicitly states the attack requires no special internal knowledge, meaning the trigger can be delivered by an adversary who is not previously familiar with the specific target's configuration, and no user interaction is required.

Attack surface and reachability. The attack vector is adjacent access — the adversary must be on the same layer-2 wireless domain as the victim (i.e., within radio range of the client or the access point it is associated with). The vulnerable component is the WiFi driver that processes 802.11 management, control, or data frames received over the air. Because the driver must parse untrusted wireless frames before they are subject to upper-layer authentication and encryption checks, an unauthenticated adjacent attacker can deliver malformed or exceptional-condition frames directly to the vulnerable parsing logic. The NVD description notes that "attack requirements are not present without special internal knowledge," indicating the exploit does not depend on prior access, credentials, or target-specific intelligence.

Technical detail limitation. The NVD description and CNA title do not disclose the specific frame type, function name, or code path involved. No public technical write-up, patch commit, or oss-security disclosure provides implementation-level detail. Analysts should therefore treat the specific trigger mechanism as unknown while recognizing the vulnerability class (improper conditions check in a kernel-mode wireless driver reachable by adjacent network input) is well understood and historically exploitable for DoS. Any claims about specific 802.11 frame subtypes, driver symbols, or register states would be speculative and are intentionally omitted.

Exploitation Scenarios

No public PoC or exploit code is available; the attack chain below is inferred from the vulnerability class and the conditions described in the NVD entry.

1. Reconnaissance / target identification. The adversary positions themselves within radio range of the target wireless network. Because the attack requires only adjacent access and no special internal knowledge, the attacker can use passive wireless monitoring to identify target networks (SSID, BSSID, channel) and likely client devices (e.g., via probe request/response traffic or association frames). The attack does not require knowledge of WPA credentials if the vulnerable processing occurs before authentication, or in open/guest network segments where unauthenticated frames are accepted by the driver.

2. Triggering the flaw. The adversary transmits crafted wireless frames (at the vulnerability-class level: a frame or sequence of frames that places the PROSet/Wireless driver in an exceptional or unusual state). Because the driver contains an improper conditions check (CWE-754), it fails to identify and gracefully handle this abnormal state. The malformed input is passed deeper into the driver's processing logic where no defensive check exists, producing a fault condition in Ring 2.

3. Execution / delivery method. This is not a memory-corruption or code-execution primitive based on available data; it is a fault-injection/state-exception DoS. The "payload" is the malformed wireless input itself rather than shellcode or a malicious binary. The NVD scoring notes confirm no confidentiality or integrity impact, so the observed outcome is limited to availability. The driver, running in kernel context, faults and triggers a system-level crash or driver-level reset.

4. Post-exploitation impact. The target system becomes unavailable (crash/restart, or loss of wireless connectivity requiring manual recovery). In an enterprise, repeated delivery of the trigger allows an attacker to cause persistent or intermittent denial of service against targeted client devices. Because no user interaction is required, the attack can be automated and repeated across multiple victims within wireless range without the attacker ever authenticating to the network.

Impact Assessment

Business impact. The primary impact is availability of wireless-enabled endpoint devices. Organizations relying on Intel-based WiFi clients (laptops, tablets, thin clients, IoT gateways with Intel wireless modules) face potential service disruption in office, manufacturing, healthcare, and public-venue environments. The vulnerability does not enable data theft, credential compromise, or lateral movement; however, chronic device reboots disrupt user productivity and can destabilize disconnected workers or devices that depend on sustained connectivity (e.g., VoIP handsets, wireless scanners).

Affected systems. The vendor has not disclosed an affected version range; all deployments of Intel PROSet/Wireless WiFi Software should be considered potentially exposed until Intel releases a security advisory. The NVD description references "some Intel(R) PROSet/Wireless WiFi Software," indicating the flaw may be limited to specific driver generations or feature sets.

Blast radius. The attack is limited to the adjacent wireless domain, so the immediate blast radius is the set of WiFi clients associated with a given access point or within physical range of the attacker. Because the adversary requires no authentication and no user interaction, the exploitation barrier is low. Per the official CVSS score and vector are N/A, and the NVD text describes the attack as adjacent-access, low-complexity, unauthenticated, and no-interaction with high availability impact — characteristics that would correspond to a moderate-severity (approximate CVSS 3.x base score of 6.5) disruptive threat if a vector were formally assigned. The EPSS score of 0.00172 (6.8th percentile) indicates low current exploitation likelihood, but this is offset by the confirmed absence of any patch, making the vulnerability a standing risk for affected fleets.

Detection Guidance

Detection for this vulnerability is challenging because the attack occurs at the 802.11 radio layer and the failure manifests as a kernel-driver fault. The most reliable telemetry is host-based: Windows Error Reporting (WER) bugcheck records and WLAN AutoConfig events referencing the Intel PROSet/Wireless components. Network-based detection is limited to radio-layer anomaly monitoring (e.g., malformed management frames or excessive deauthentication/disassociation activity) as a class-level proxy for adjacent wireless DoS.

Sigma Rule

title: Intel PROSet/Wireless WiFi Driver Crash - Potential Exploitation of CVE-2026-20776
id: 7f3b1b3c-9d4e-4f2a-8b1d-1c5e9a2b6d4f
status: experimental
description: Detects repeated Windows Error Reporting crash events or WLAN AutoConfig failures referencing Intel PROSet/Wireless WiFi components, potentially indicating an adjacent denial-of-service attempt against the wireless driver.
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2026-20776
author: ValtersIT Threat Intelligence
date: 2026/06/01
logsource:
    product: windows
    service: wer
    category: application
detection:
    selection_wer:
        EventID: 1001
        Provider_Name: 'Windows Error Reporting'
        Message|contains:
            - 'PROSet'
            - 'Wireless'
            - 'WLAN'
            - 'wlan'
    selection_wlan_config:
        Provider_Name: 'Microsoft-Windows-WLAN-AutoConfig'
        Message|contains:
            - 'disconnect'
            - 'failure'
            - 'reset'
    condition: selection_wer or selection_wlan_config
    timeframe: 15m
falsepositives:
    - Legitimate driver crashes caused by outdated firmware or hardware faults
    - Expected WLAN disconnections during network roaming or maintenance
level: high
fields:
    - ComputerName
    - Message
    - Provider_Name
tags:
    - attack.t1499
    - cve.2026-20776
    - cwe.754

YARA Rule

rule intel_proset_wireless_dos_cve_2026_20776
{
    meta:
        author = "ValtersIT Threat Intelligence"
        description = "Detects crash artifacts and memory dump strings referencing Intel PROSet/Wireless WiFi driver failures consistent with CVE-2026-20776"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-20776"
        cve = "2026-20776"
        date = "2026-06-01"
    strings:
        $s1 = "PROSet/Wireless" ascii wide nocase
        $s2 = "Intel(R) WiFi" ascii wide nocase
        $s3 = "WLAN" ascii wide nocase
        $s4 = "BugCheck" ascii wide nocase
        $s5 = "DRIVER_FAULT" ascii wide nocase
    condition:
        uint16(0) == 0x5A4D and any of ($s1, $s2) and (any of ($s3, $s4, $s5))
}

Suricata IDS Rule

alert ieee80211 any any -> any any (msg:"CVE-2026-20776 - Potential Adjacent Wireless DoS Against Intel WiFi Clients - Deauthentication Flood"; ieee80211.type_subtype:12; threshold: type both, track by_src, count 100, seconds 10; classtype:attempted-dos; reference:cve,2026-20776; sid:5432101; rev:1;)

The rule above is a class-level detection: CVE-2026-20776 is triggered by an adjacent, unauthenticated adversary delivering exceptional-condition wireless input to the Intel PROSet/Wireless driver. Because the specific frame type is undisclosed, hunting for abnormal volume or malformed 802.11 management frames (deauthentication subtype 12 being the classic adjacent DoS vector) is the appropriate network-layer proxy. Adjust the threshold to site-specific wireless traffic baselines to reduce false positives in dense environments.

Elastic Detection

sequence by host.name with maxspan=15m
  [ any where event.code == "1001" and message like "*PROSet*" ]
  [ any where event.code == "1001" and message like "*PROSet*" ]
  [ any where event.code == "1001" and message like "*PROSet*" ]

This EQL query correlates three or more Windows Error Reporting events (Event ID 1001) mentioning the Intel PROSet component within a 15-minute window, indicating repeat WiFi driver crashes consistent with an automated or replayed adjacent DoS attempt. For environments that collect WLAN AutoConfig telemetry, add an additional sequence step matching Provider Name: Microsoft-Windows-WLAN-AutoConfig with disconnection- or reset-related messages to enrich the crash correlation.

Splunk SPL Query

index=windows (source="WinEventLog:Application" OR source="XmlWinEventLog:Microsoft-Windows-WER-SystemErrorReporting/Operational") EventCode=1001 "PROSet" OR "Wireless"
| bucket _time span=15m
| stats count as crash_count dc(_time) as distinct_windows by host, _time
| where crash_count >= 3
| sort - crash_count
| table _time, host, crash_count, distinct_windows

For wider visibility across the wireless fleet:

index=windows EventCode=1001 OR "WLAN-AutoConfig"
| search "PROSet" OR "Wireless" OR "wlan"
| stats count by host, source
| where count > 5
| table host, source, count

The first query detects burst activity of WER crash events per host, a strong signal of repeated driver faults. The second provides a fleet-wide baseline of driver failure events so security teams can identify outlier hosts suffering persistent WiFi stack crashes.

Wazuh OSSEC Rule

<group name="windows,denial_of_service,">
  <rule id="100345" level="10">
    <decoded_as>windows-event-channel</decoded_as>
    <field name="win.system.eventID">1001</field>
    <match>PROSet|Wireless|WLAN|wlan</match>
    <description>Intel PROSet/Wireless WiFi driver crash detected - possible CVE-2026-20776 adjacent denial-of-service</description>
    <options>no_full_log</options>
    <group>cve_2026_20776,cwe_754,denial_of_service,</group>
  </rule>

  <rule id="100346" level="6" frequency="3" timeframe="900">
    <if_matched_sid>100345</if_matched_sid>
    <description>Repeat Intel PROSet/Wireless WiFi driver crashes within 15 minutes - potential active exploitation</description>
    <group>cve_2026_20776,denial_of_service,</group>
  </rule>
</group>

The first rule fires at level 10 on a single crash event referencing the Intel PROSet/Wireless components through the Windows Event Channel decoder. The second rule escalates to a frequency-based alert when three or more matching crash events occur within 15 minutes, correlating with an automated or replayed attack pattern.

Mitigation & Patch Guidance

Patch confidence: 0/4 — UNPATCHED. No patch evidence exists from any tracked source, and Intel has not published a security advisory, fixing version, or affected-version disclosure for CVE-2026-20776. Organizations should treat all Intel PROSet/Wireless WiFi Software deployments as potentially affected.

1. Immediate mitigations (no vendor fix available):

   • Restrict adjacent-network exposure: enforce WPA2/WPA3-Enterprise with 802.11w (Protected Management Frames) where supported to reduce the feasibility of injecting management frames; treat open/guest SSIDs as high-risk and isolate them from corporate clients.
   • Deploy host-based monitoring for WER/WLAN AutoConfig crash events using the detection rules above; escalate hosts exhibiting repeated WiFi driver crashes as suspected DoS victims.
   • Segment wireless networks and limit the density of high-value endpoints on a single SSID/AP so a broadcast-grade DoS affects a smaller blast radius.
   • Where operational risk is unacceptable and the device supports it, disable WiFi when a wired connection is available.

2. Patch/upgrade steps:

   • Monitor Intel's Product Security Center (INTC-SA advisories) and the NVD record for CVE-2026-20776 for the first official fix.
   • Do not apply third-party driver replacements or unofficial "patch" binaries claiming to address this CVE; with 0/4 patch confidence, no validated patch exists.
   • When a fix is released, prioritize fleet rollout using the organization's standard driver management workflow (e.g., Intune, SCCM, or Intel Driver & Support Assistant), beginning with high-risk users (frequent travelers, executive staff, field workers on open networks).

3. Long-term hardening:

   • Establish a driver baseline and enforce updates via enterprise management tooling so WiFi driver versions are centrally tracked and rapidly replaceable.
   • Enable Windows crash dump collection (kernel and small memory dumps) on high-value endpoints and retain WER records for forensic correlation of future wireless DoS events.
   • Monitor CISA KEV for CVE-2026-20776 listing; if the CVE is added, treat exploitation as confirmed in the wild and accelerate mitigation to network-level controls (e.g., wireless intrusion prevention) in addition to endpoint monitoring.
   • Incorporate adjacent-access DoS scenarios into wireless penetration testing and purple-team exercises; verify that existing wireless IPS/IDS can log and alert on malformed management frames and deauthentication floods.

References

1. NVD Entry — https://nvd.nist.gov/vuln/detail/CVE-2026-20776
2. CVE.org Record — https://www.cve.org/CVERecord?id=CVE-2026-20776
3. CWE-754 MITRE — https://cwe.mitre.org/data/definitions/754.html
4. Intel Product Security Center (monitor for future INTC-SA advisory) — https://www.intel.com/content/www/us/en/security-center/default.html
5. FIRST EPSS (CVE-2026-20776 scoring) — https://www.first.org/epss/

Campaign and exploitation status: No known threat actor campaigns, exploit-in-the-wild evidence, or CISA KEV inclusion exists for CVE-2026-20776 as of the writing of this report. The vulnerability remains unpatched with no public PoC; organizations downgrade immediate risk accordingly but should prioritize the mitigations above given the low exploitation barrier (adjacent access, unauthenticated, no user interaction) once exploit techniques become public.