SecOps SignalSecurity Intelligence Workspace
Loading collection status
Vulnerabilities/CVE-2018-8639Public Intelligence Dossier
Source: microsoft · Limited verification•Last verified: •Collection Degraded
CVE-2018-8639ListedHIGH (raw)CVSS 8.4CWE-404

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka "Win32k Elevation of Privilege Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2019, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers

Published: 12 Dec 2018•Last updated: 17 Jun 2026, 07:35 AM IST•Source identifier: secure@microsoft.com
Dossier completeness: source-provided sections 3 / 3 · rule guidance available. Missing source facts count as incomplete.
Official source
CISA KEV catalog
Listed
Added03 Mar 2025
Due24 Mar 2025
RansomwareKnown
CVSS score
8.4HIGH (raw)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Metric source134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS probability
22.2%0.222
Percentile98th
Weakness type
CWE-404
No further CWE recorded
Remediation
Patch status unknown
No fixed version or KB recorded

Why It Matters

Analysis dossier

Why It Matters

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka "Win32k Elevation of Privilege Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2019, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers. This CVE ID is unique from CVE-2018-8641.

SOC priority

Immediate Attention

Actively exploited (source statement)

Yes

Publicly disclosed

Unknown

Risk basis: CISA KEV exploitation signal; Microsoft or Microsoft-managed product relevance; HIGH severity; Known exploitation signal from CISA KEV or ransomware metadata; Source-confirmed exploitation or CISA KEV/ransomware metadata

Affected Products & Remediation

13 source-backed products
Affected products and versions (source)
  • microsoft windows 10 1507 · version range not provided by source · NVD CPE · Source
  • microsoft windows 10 1607 · version range not provided by source · NVD CPE · Source
  • microsoft windows 10 1703 · version range not provided by source · NVD CPE · Source
  • microsoft windows 10 1709 · version range not provided by source · NVD CPE · Source
  • microsoft windows 10 1803 · version range not provided by source · NVD CPE · Source
  • microsoft windows 10 1809 · version range not provided by source · NVD CPE · Source
  • microsoft windows 7 · version range not provided by source · NVD CPE · Source
  • microsoft windows 8.1 · version range not provided by source · NVD CPE · Source
  • microsoft windows rt 8.1 · version range not provided by source · NVD CPE · Source
  • microsoft windows server 2008 · r2 · NVD CPE · Source
  • microsoft windows server 2012 · r2 · NVD CPE · Source
  • microsoft windows server 2016 · version range not provided by source · NVD CPE · Source
  • microsoft windows server 2019 · version range not provided by source · NVD CPE · Source
Recorded patch / KBNot provided by source

Vendor or catalog guidance (source)

  • CISA KEV: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Known exploitation (source facts)

Only what a source states. Unknown means no source has said either way; it is not "not exploited".

CISA KEV
Listed
Exploited (source statement)
Yes
Publicly disclosed (source)
Unknown

CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Suggested hunting (rule-based inference)

SecOps Signal recommendation (rule-based inference). These steps are hunting hypotheses from the vulnerability class; they do not state or imply that exploitation occurred here or anywhere.

Matched microsoft-enterprise (Affected product: microsoft windows 10 1507, Vendor: microsoft)

Exposure

  1. Identify affected Microsoft products and compare local builds with the MSRC advisory.Telemetry: DeviceTvmSoftwareVulnerabilities · The MSRC product/build mapping establishes applicability. · Rule microsoft-enterprise

Exploitation evidence

  1. Review the advisory's documented behavior on matching hosts before selecting a hunt.Telemetry: DeviceProcessEvents · Product family alone does not justify a CVE-specific detection. · Rule microsoft-enterprise

Response

  1. Confirm the source-stated KB or mitigation on matching assets.Telemetry: DeviceTvmSoftwareVulnerabilities · A post-update inventory check verifies remediation. · Rule microsoft-enterprise

CISA KEV Record

Catalog entry
03 Mar 2025
Required action due
24 Mar 2025
Known ransomware use
Known

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Change History & Source Data

— No recorded material change

CNA / source
secure@microsoft.com
Record status · verification
UPDATED · Microsoft primary source linked; CISA KEV confirmed
CPE
cpe:2.3:o:microsoft:windows_10_1507:-:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_10_1607:-:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_10_1703:-:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_10_1709:-:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_10_1803:-:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_10_1809:-:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:pro_n:*:*:*, cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*

Evidence & Provenance

4 public sources
CISA KEV CatalogAdded 2025-03-03portal.msrc.microsoft.comSource recordnvd.nist.govSource recordcisa.govSource record

Linked by the query's stored exact CVE association. Review required tables and validation status before use.

Detection Hunting Query
Target: DeviceTvmSoftwareVulnerabilities•Defender XDR
Detect endpoints exposed to CVE-2018-8639
Purpose: Exposure assessment (Category: Exposure Check)Why linked: Query metadata names CVE-2018-8639
DeviceTvmSoftwareVulnerabilities| where CveId == "CVE-2018-8639"| project DeviceId, DeviceName, OSPlatform, OSVersion, SoftwareVendor, SoftwareName, SoftwareVersion, CveId, VulnerabilitySeverityLevel, RecommendedSecurityUpdate, RecommendedSecurityUpdateId| sort by VulnerabilitySeverityLevel desc
Schema Checked · Not runtime validatedSource: SecOps Signal deterministic template · Limited verificationStatic screening: Passed structure and schema checks; tenant execution is not verified.
Open KQL Library

Looking up related community queries…

Loading related intelligence

Correlated briefings

SecOps Signal surfaces public advisory facts only. A missing value means the source has not published it, not that your environment is unaffected. No tenant inventory is connected.