BlackTreeCVE Intelligence
← Back to the CVE catalogue
Full vulnerability report · 2021
CVE-2021-34508High confidence

Windows Kernel Remote Code Execution Vulnerability

Microsoft · Windows 10 Version 1809

8.8HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-21162

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

Windows Kernel Remote Code Execution Vulnerability

What

Windows Kernel Remote Code Execution Vulnerability

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may execute code or commands in the affected security context.

What

Windows Kernel Remote Code Execution Vulnerability

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may execute code or commands in the affected security context.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → vulnerable operation → execute code or commands in the affected security context
Attack surface
Network
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration.
CWE not yet assigned
CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
After compromise, an attacker may use built-in shells, scripting engines, scheduled tasks and native network utilities for discovery, persistence or movement. This is a plausible LoTL path, not evidence that it has occurred for every attack.
NetworkRemote code execution
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

Cyber Security Agency of Singapore · English · CSA-SB-20210721Security Bulletin 21 Jul 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 21 Jul 2021, published on 21 July 2021. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-520Multiples vulnérabilités dans Microsoft Windows

d?id=CVE-2021-34494 Référence CVE CVE-2021-34496 https://www.cve.org/CVERecord?id=CVE-2021-34496 Référence CVE CVE-2021-34497 https://www.cve.org/CVERecord?id=CVE-2021-34497 Référence CVE CVE-2021-34498 https://www.cve.org/CVERecord?id=CVE-2021-34498 Référence CVE CVE-2021-34499 https://www.cve.org/CVERecord?id=CVE-2021-34499 Référence CVE CVE-2021-34500 https://www.cve.org/CVERecord?id=CVE-2021-34500 Référence CVE CVE-2021-34503 https://www.cve.org/CVERecord?id=CVE-2021-34503 Référence CVE CVE-2021-34504 https://www.cve.org/CVERecord?id=CVE-2021-34504 Référence CVE CVE-2021-34507 https://www.cve.org/CVERecord?id=CVE-2021-34507 Référence CVE CVE-2021-34508 https://www.cve.org/CVERecord?id=CVE-2021-34508 Référence CVE CVE-2021-34509 https://www.cve.org/CVERecord?id=CVE-2021-34509 Référence CVE CVE-2021-34510 https://www.cve.org/CVERecord?id=CVE-2021-34510 Référence CVE CVE-2021-34511 https://www.cve.org/CVERecord?id=CVE-2021-34511 Référence CVE CVE-2021-34512 https://www.cve.org/CVERecord?id=CVE-2021-34512 Référence CVE CVE-2021-34513 https://www.cve.org/CVERecord?id=CVE-2021-34513 Référence CVE CVE-2021-34514 https://www.cve.org/CVERecord?id=CVE-2021-34514 Référence CVE CVE-2021-34516 https://www.cve.org/CVERecord?id=CVE-2021-34516 Référence CVE CVE-2021-34521 https://www.cve.org/CVERecord?id=

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-002206Microsoft Windows Server におけるリモートでコードを実行される脆弱性

Microsoft Windows Server には、Windows カーネルに不備があるため、リモートでコードを実行される脆弱性が存在します。 本脆弱性は、CVE-2021-34508 とは異なる脆弱性です。

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-002139Microsoft Windows 10 および Windows Server におけるリモートでコードを実行される脆弱性

Microsoft Windows 10 および Windows Server には、Windows カーネルに不備があるため、リモートでコードを実行される脆弱性が存在します。 本脆弱性は、CVE-2021-34458 とは異なる脆弱性です。

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-5338MS 7월 보안 위협에 따른 정기 보안 업데이트 권고

Defender 원격 코드 실행 취약성 Windows Defender CVE-2021-34464 Microsoft Defender 원격 코드 실행 취약성 Windows Desktop Bridge CVE-2021-33759 Windows 데스크톱 브리지 권한 상승 취약성 Windows Event Tracing CVE-2021-33774 Windows 이벤트 추적 권한 상승 취약성 Windows File History Service CVE-2021-34455 Windows 파일 기록 서비스 권한 상승 취약성 Windows Hello CVE-2021-34466 Windows Hello 보안 기능 우회 취약성 Windows HTML Platform CVE-2021-34446 Windows HTML 플랫폼 보안 기능 우회 취약성 Windows Installer CVE-2021-34511 Windows Installer 권한 상승 취약성 Windows Installer CVE-2021-33765 Windows 설치 관리자 스푸핑 취약성 Windows Installer CVE-2021-31961 Windows 설치 서비스 권한 상승 취약성 Windows Kernel CVE-2021-34514 Windows 커널 권한 상승 취약성 Windows Kernel CVE-2021-34508 Windows 커널 원격 코드 실행 취약성 Windows Kernel CVE-2021-34500 Windows 커널 메모리 정보 유출 취약성 Windows Kernel CVE-2021-34461 Windows 컨테이너 분리 FS 필터 드라이버 권한 상승 취약성 Windows Kernel CVE-2021-34458 Windows 커널 원격 코드 실행 취약성 Windows Kernel CVE-2021-33771 Windows 커널 권한 상승 취약성 Windows Kernel CVE-2021-31979 Windows 커널 권한 상승 취약성 Windows Key Distribution Center CVE-2021-33764 Windows 키 배포 센터 정보 유출 취약성 Windows Local Security Authority Subsystem Service CVE-2021-33788 Windows LSA 서비스 거부 취약성 Windows Local Security Authority Subsystem Service CVE-2021-33786 Windows LSA 보안 기능 우회 취약성 Windows MSHTML Platform CVE-2021-34497 Windows MSHTML 플랫폼 원격 코드 실행 취약성 Windows MSHTML Platform

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 14 Jul 2021 · Last source change 10 Aug 2026, 15:11 UTC · CWE not yet assigned

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-21162
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceUnavailable
NVD statusNVD modified after enrichment

Missing structured fields: CWE classification. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-21162↗Patch or update reference↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-34508 · cve.blacktree.nl