CriticalCVE-2026-32202

Windows Shell Spoofing Vulnerability (CVE-2026-32202)

Published 14.04.2026Last modified 26.10.2026In CISA KEV since 28.04.2026Sources: pwn.watch, CVE.org, Msrc Update Guide, EUVD, BSI

What is affected, what to do

Protection mechanism failure in Windows Shell allows an unauthorized attacker to perform spoofing over a network.

The vulnerability is being actively exploited; treat it as a priority. Update Microsoft Windows 10 Version 1607 to version 10.0.14393.9339, Microsoft Windows 10 Version 1809 to version 10.0.17763.9020, Microsoft Windows 10 Version 21H2 to version 10.0.19044.7548. Immediate actions, mitigation and detection rules are in the runbook below.

Affected: Microsoft Windows 10 Version 1607 lt 10.0.14393.0..10.0.14393.9339
Microsoft Windows 10 Version 1809 lt 10.0.17763.0..10.0.17763.9020
Microsoft Windows 10 Version 21H2 lt 10.0.19044.0..10.0.19044.7548
Microsoft Windows 10 Version 22H2 lt 10.0.19045.0..10.0.19045.7548
Microsoft Windows 11 version 23H2 lt 10.0.22631.0..10.0.22631.7376
Microsoft Windows 11 Version 24H2 lt 10.0.26100.0..10.0.26100.8875
Microsoft Windows 11 Version 25H2 lt 10.0.26200.0..10.0.26200.8875
Microsoft Windows 11 version 26H1 lt 10.0.28000.0..10.0.28000.2525
Microsoft Windows Server 2012 lt 6.2.9200.0..6.2.9200.26226
Microsoft Windows Server 2012 (Server Core installation) lt 6.2.9200.0..6.2.9200.26226
Microsoft Windows Server 2012 R2 lt 6.3.9600.0..6.3.9600.23291
Microsoft Windows Server 2012 R2 (Server Core installation) lt 6.3.9600.0..6.3.9600.23291
Microsoft Windows Server 2016 lt 10.0.14393.0..10.0.14393.9339
Microsoft Windows Server 2016 (Server Core installation) lt 10.0.14393.0..10.0.14393.9339
Microsoft Windows Server 2019 lt 10.0.17763.0..10.0.17763.9020
Microsoft Windows Server 2019 (Server Core installation) lt 10.0.17763.0..10.0.17763.9020
Microsoft Windows Server 2022 lt 10.0.20348.0..10.0.20348.5386
Microsoft Windows Server 2025 lt 10.0.26100.0..10.0.26100.33158
Microsoft Windows Server 2025 (Server Core installation) lt 10.0.26100.0..10.0.26100.33158
Fixed in: Microsoft Windows 10 Version 1607 10.0.14393.9339
Microsoft Windows 10 Version 1809 10.0.17763.9020
Microsoft Windows 10 Version 21H2 10.0.19044.7548
Microsoft Windows 10 Version 22H2 10.0.19045.7548
Microsoft Windows 11 version 23H2 10.0.22631.7376
Microsoft Windows 11 Version 24H2 10.0.26100.8875
Microsoft Windows 11 Version 25H2 10.0.26200.8875
Microsoft Windows 11 version 26H1 10.0.28000.2525
Microsoft Windows Server 2012 6.2.9200.26226
Microsoft Windows Server 2012 (Server Core installation) 6.2.9200.26226
Microsoft Windows Server 2012 R2 6.3.9600.23291
Microsoft Windows Server 2012 R2 (Server Core installation) 6.3.9600.23291
Microsoft Windows Server 2016 10.0.14393.9339
Microsoft Windows Server 2016 (Server Core installation) 10.0.14393.9339
Microsoft Windows Server 2019 10.0.17763.9020
Microsoft Windows Server 2019 (Server Core installation) 10.0.17763.9020
Microsoft Windows Server 2022 10.0.20348.5386
Microsoft Windows Server 2025 10.0.26100.33158
Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.33158

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Metrics

4.3

Priority

XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

Source: NVD, CVSS v3

4.3

CVSS v3

Severity Medium on the scale from 0 to 10.

Source: pwn.watch, CVE.org, Msrc Update Guide, EUVD, BSI

70.9 %

EPSS score

High — model estimates ≥ 50% chance of real-world exploitation within 30 days.

Source: FIRST EPSS, percentile 99.40

Show all metrics

Severity: Critical
Priority (0–325) The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first? Read in glossary: 216.86 Methodology
Exploit maturity An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack. Read in glossary: actively exploitedSource: VulnCheck KEV (opens in a new tab) How we classify
XIEM Effective CVSS XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command. Read in glossary: 4.3 Methodology
CVSS v3 CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions. Read in glossary: 4.3
EPSS score The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“. Read in glossary: 70.9 %; High — model estimates ≥ 50% chance of real-world exploitation within 30 days.
EPSS percentile The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking. Read in glossary: 99.40; Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
KEV status The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching. Read in glossary: Actively exploited
Published: 14.04.2026
In CISA KEV since The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching. Read in glossary: 28.04.2026
CWE CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect. Read in glossary: CWE-693

Response and mitigation

Why act now?

Prioritisation rationale

On paper the severity is moderate: the flaw is network-reachable without authentication, but it needs user interaction and has only limited confidentiality impact. Its KEV listing and high exploitation likelihood show that attackers use it in practice as one link in phishing chains, either to bypass Shell security prompts or to harvest credentials such as NTLM hashes for later relay or cracking. CISA does not flag known ransomware use. Organisations with broad email exposure, permissive outbound SMB/NTLM or hybrid AD should patch on an expedited cycle within days. Where egress SMB is already blocked and NTLM is restricted, rating it "high but not critical" is defensible.

01
Runbook step 1
Immediate response (0-24 h)
- Deploy the cumulative security update and verify the minimum builds: Windows 10 1607 ≥ 10.0.14393.9339, 1809 ≥ 10.0.17763.9020, 21H2 ≥ 10.0.19044.7548, 22H2 ≥ 10.0.19045.7548, Windows 11 23H2 ≥ 10.0.22631.7376, 24H2 ≥ 10.0.26100.8875, 25H2 ≥ 10.0.26200.8875, 26H1 ≥ 10.0.28000.2525. Look up the exact KB number in the Microsoft Security Update Guide. Check server editions sharing the 1607/1809 build lines as well.
- Patch high-risk endpoints first: mail and browser-heavy clients, executive and admin workstations, and RDS/VDI hosts. Users on these systems open untrusted content, so they are the most likely to provide the required user interaction.
- Query build compliance through Intune, SCCM or Defender TVM. Raise every unpatched internet-connected host as an open finding in vulnerability management.
- Block outbound SMB to the internet (TCP 445/139) at the perimeter if it is not already blocked. Windows Shell spoofing flaws are typically abused through crafted shortcut or container files that make the client reach out to attacker-controlled hosts.
- Tighten the mail gateway: quarantine attachments and archive contents containing .lnk, .url, .library-ms, .search-ms, .searchConnector-ms and .scf.
02
Runbook step 2
Mitigation layers
- Network segmentation: Restrict outbound SMB (445/139) and WebDAV (80/443 from the WebClient service) to known internal file servers only. Configure client VLAN egress rules so that SMB is permitted only to defined server subnets.
- IAM / authentication: Set the GPO "Network security: Restrict NTLM: Outgoing NTLM traffic to remote servers" to "Audit all" first, then move to "Deny all" with an exception list. Add privileged accounts to "Protected Users". Enforce SMB signing.
- Endpoint hardening: Disable the WebClient service wherever WebDAV is not needed. Enforce Microsoft Defender SmartScreen and Mark-of-the-Web handling via GPO, with user overrides disabled. Enable the ASR rule "Block executable content from email client and webmail".
- Configuration: Restrict automatic extraction and preview of untrusted archives. Disable Explorer preview handlers for Internet-zone files via policy.
- Web/proxy layer: Block downloads of the Shell file types listed above at the secure web gateway. The vendor advisory provides no specific IPS signatures; enable generic Suricata rules for outbound SMB/NTLMSSP to the internet.
03
Runbook step 3
Detection rules
- Sysmon EID 3 / MDE DeviceNetworkEvents: explorer.exe connecting to public IPs on port 445. KQL: DeviceNetworkEvents | where RemotePort in (445,139) and RemoteIPType == "Public" and InitiatingProcessFileName =~ "explorer.exe"
- NTLM auditing: Microsoft-Windows-NTLM/Operational EID 8001 (outbound NTLM authentication) where the target server is outside your domain or IP space. Correlate with Security EID 4648 showing an external target name.
- Sysmon EID 11 (FileCreate): creation of .lnk, .url, .library-ms or .search-ms files under \Downloads\, \AppData\Local\Temp\ or archive-tool extraction paths. Sigma shape: TargetFilename|endswith: ['.library-ms','.url','.search-ms'] AND Image|endswith: ['\outlook.exe','\explorer.exe','\7zFM.exe','\WinRAR.exe']
- Zeek/Suricata: entries in ntlm.log or smb_mapping.log with id.resp_h outside RFC1918. Also watch for HTTP requests with User-Agent Microsoft-WebDAV-MiniRedir to unfamiliar domains.
- EDR process ancestry: rundll32.exe loading davclnt.dll,DavSetCookie shortly after a file is opened from the mail client. This pattern indicates a WebDAV callback triggered by a crafted shortcut.

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2 NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management. Read in glossary: Actively exploited: treat the vulnerability as a priority in vulnerability handling under Art. 21(2)(e) NIS2. If it is exploited in your environment, check the reporting obligation under Art. 23 (early warning within 24 hours).
CRA The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates. Read in glossary: Since 11.09.2026, manufacturers of affected products with digital elements must report actively exploited vulnerabilities under Art. 14 CRA, with an early warning within 24 hours via ENISA's single reporting platform.
ISO/IEC 27001 ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security. Read in glossary: Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

Protection mechanism failure in Windows Shell allows an unauthorized attacker to perform spoofing over a network.

Source: pwn.watch, cvelistv5, Microsoft Security Update Guide, ENISA EUVD, NVD (NIST), CISA KEV Catalog, CVE.org (MITRE), BSI WID Portal, BSI CSAF

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

Affected products
		Affected versions	Fixed in
Microsoft	Windows 10 Version 1607	`10.0.14393.0 – < 10.0.14393.9339`	`10.0.14393.9339`
Microsoft	Windows 10 Version 1809	`10.0.17763.0 – < 10.0.17763.9020`	`10.0.17763.9020`
Microsoft	Windows 10 Version 21H2	`10.0.19044.0 – < 10.0.19044.7548`	`10.0.19044.7548`
Microsoft	Windows 10 Version 22H2	`10.0.19045.0 – < 10.0.19045.7548`	`10.0.19045.7548`
Microsoft	Windows 11 version 23H2	`10.0.22631.0 – < 10.0.22631.7376`	`10.0.22631.7376`
Microsoft	Windows 11 Version 24H2	`10.0.26100.0 – < 10.0.26100.8875`	`10.0.26100.8875`
Microsoft	Windows 11 Version 25H2	`10.0.26200.0 – < 10.0.26200.8875`	`10.0.26200.8875`
Microsoft	Windows 11 version 26H1	`10.0.28000.0 – < 10.0.28000.2525`	`10.0.28000.2525`
Microsoft	Windows Server 2012	`6.2.9200.0 – < 6.2.9200.26226`	`6.2.9200.26226`
Microsoft	Windows Server 2012 (Server Core installation)	`6.2.9200.0 – < 6.2.9200.26226`	`6.2.9200.26226`
Microsoft	Windows Server 2012 R2	`6.3.9600.0 – < 6.3.9600.23291`	`6.3.9600.23291`
Microsoft	Windows Server 2012 R2 (Server Core installation)	`6.3.9600.0 – < 6.3.9600.23291`	`6.3.9600.23291`
Microsoft	Windows Server 2016	`10.0.14393.0 – < 10.0.14393.9339`	`10.0.14393.9339`
Microsoft	Windows Server 2016 (Server Core installation)	`10.0.14393.0 – < 10.0.14393.9339`	`10.0.14393.9339`
Microsoft	Windows Server 2019	`10.0.17763.0 – < 10.0.17763.9020`	`10.0.17763.9020`
Microsoft	Windows Server 2019 (Server Core installation)	`10.0.17763.0 – < 10.0.17763.9020`	`10.0.17763.9020`
Microsoft	Windows Server 2022	`10.0.20348.0 – < 10.0.20348.5386`	`10.0.20348.5386`
Microsoft	Windows Server 2025	`10.0.26100.0 – < 10.0.26100.33158`	`10.0.26100.33158`
Microsoft	Windows Server 2025 (Server Core installation)	`10.0.26100.0 – < 10.0.26100.33158`	`10.0.26100.33158`
Xerox	FreeFlow Print Server	`v7` `v2`	— —

Vendors and products

Affected operating systems

Affected operating systems

Windows	microsoft	windows_10_1607	—
Windows	microsoft	windows_10_1809	—
Windows	microsoft	windows_10_21h2	—
Windows	microsoft	windows_10_22h2	—
Windows	microsoft	windows_11_23h2	—
Windows	microsoft	windows_11_24h2	—
Windows	microsoft	windows_11_25h2	—
Windows	microsoft	windows_11_26h1	—
Windows	microsoft	windows_server_2012	`r2`
Windows	microsoft	windows_server_2012	—
Windows	microsoft	windows_server_2016	—
Windows	microsoft	windows_server_2019	—
Windows	microsoft	windows_server_2022	—
Windows	microsoft	windows_server_2022_23h2	—
Windows	microsoft	windows_server_2025	—

Weakness classes (CWE)

CWE-693Protection Mechanism Failure
Pillar
The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product.
Entry at MITRE CWE-693

Public exploit references

Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

Public exploit references

CISA KEV Catalog	CISA Known Exploited Vulnerability (opens in a new tab)cisa.gov	actively exploited	28.04.2026

References & sources

Microsoft Security Update GuideWindows Shell Spoofing Vulnerabilityeuvd, Vendor advisory, Patch, Vendor advisory
cisa.govknown-exploited-vulnerabilities-catalog?field_cve=CVE-2026-32202government-resource, Third-party advisory, US government resource
vicarius.iovsociety/posts/cve-2026-32202-detection-script-spoofing-vulnera…Third-party advisory
vicarius.iovsociety/posts/cve-2026-32202-mitigation-script-spoofing-vulner…Mitigation, Third-party advisory
pwn.watchpwn.watch: Microsoft Windows: Microsoft Windows Protection Mechanism Failure Vulnerabilitypwn-watch
Microsoft Security Update GuideMicrosoft Windows — CVE-2026-32202pwn-watch
NVD (NIST)NVD: CVE-2026-32202pwn-watch
cisa.govCISA Known Exploited Vulnerabilities Catalogpwn-watch

Changes to this CVE

Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

One NVD translation into another language is hidden.

Linked advisories

October Patch Tuesday roundup: Over 1,400 Microsoft holes to be plugged, including three zero daysCSO Online14.10.2026
Follow-ups: Colorado Bill to Amend Right-to-Repair Postponed Indefinitely; French Authorities Investigate Suspect in Connection with ANTS BreachSANS NewsBites29.04.2026

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<a href="https://intel.neosec.eu/en/cve/CVE-2026-32202"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-32202.svg?lang=en" alt="CVE-2026-32202 – NEOSEC Intel" height="20"></a>

What is affected, what to do

Metrics

Response and mitigation

Prioritisation rationale

Immediate response (0-24 h)

Mitigation layers

Detection rules

Detection rules

Classification under NIS2 and CRA

Description

Affected products

Vendors and products

Affected operating systems

Weakness classes (CWE)

Public exploit references

References & sources

Changes to this CVE

Linked advisories