CVE-2021-34486

mediumpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.093 · 95 %ileexploit · PoCEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV · 2 exploits · PoC

Likely / severe?

9.25% (95th) EPSS

CVSS 4.6 · medium

Is it mine?

63 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · msrc_csaf

added 2022-03-28remediate by 2022-04-18

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-26

Microsoft Windows Event Tracing Privilege Escalation Vulnerability

Windows Event Tracing Elevation of Privilege Vulnerability

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedWindows 10 Version 1809 for 32-bit Systemsmsrc_csaf
10.0.17763.2114:Security Update:https://support.microsoft.com/help/5005030
https://support.microsoft.com/help/5005030
FixedWindows 10 Version 1809 for ARM64-based Systemsmsrc_csaf
10.0.17763.2114:Security Update:https://support.microsoft.com/help/5005030
https://support.microsoft.com/help/5005030
FixedWindows 10 Version 1809 for x64-based Systemsmsrc_csaf
10.0.17763.2114:Security Update:https://support.microsoft.com/help/5005030
https://support.microsoft.com/help/5005030
FixedWindows 10 Version 1909 for 32-bit Systemsmsrc_csaf
10.0.18363.1734:Security Update:https://support.microsoft.com/help/5005031
https://support.microsoft.com/help/5005031
FixedWindows 10 Version 1909 for ARM64-based Systemsmsrc_csaf
10.0.18363.1734:Security Update:https://support.microsoft.com/help/5005031
https://support.microsoft.com/help/5005031
FixedWindows 10 Version 1909 for x64-based Systemsmsrc_csaf
10.0.18363.1734:Security Update:https://support.microsoft.com/help/5005031
https://support.microsoft.com/help/5005031
FixedWindows 10 Version 2004 for 32-bit Systemsmsrc_csaf
10.0.19041.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033
FixedWindows 10 Version 2004 for ARM64-based Systemsmsrc_csaf
10.0.19041.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033
FixedWindows 10 Version 2004 for x64-based Systemsmsrc_csaf
10.0.19041.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033
FixedWindows 10 Version 20H2 for 32-bit Systemsmsrc_csaf
10.0.19042.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033
FixedWindows 10 Version 20H2 for ARM64-based Systemsmsrc_csaf
10.0.19042.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033
FixedWindows 10 Version 21H1 for 32-bit Systemsmsrc_csaf
10.0.19043.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033
FixedWindows 10 Version 21H1 for ARM64-based Systemsmsrc_csaf
10.0.19043.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033
FixedWindows 10 Version 21H1 for x64-based Systemsmsrc_csaf
10.0.19043.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033
FixedWindows Server 2019msrc_csaf
10.0.17763.2114:Security Update:https://support.microsoft.com/help/5005030
https://support.microsoft.com/help/5005030
FixedWindows Server 2019 (Server Core installation)msrc_csaf
10.0.17763.2114:Security Update:https://support.microsoft.com/help/5005030
https://support.microsoft.com/help/5005030
FixedWindows Server, version 2004 (Server Core installation)msrc_csaf
10.0.19041.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033
FixedWindows Server, version 20H2 (Server Core Installation)msrc_csaf
10.0.19042.1165:Security Update:https://support.microsoft.com/help/5005033
https://support.microsoft.com/help/5005033

cvss

Technical severity, 0–10. One row per scoring source.

7.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.6–7.8

v2.04.6mediumAV:L/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 3.9 · impact 6.4

v2.04.6mediumAV:L/AC:L/Au:N/C:P/I:P/A:P/E:Hsecondary · CVSS-BT (t0sche)

v3.17.8highAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · secure@microsoft.com USexploitability 1.8 · impact 5.9

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:Csecondary · Microsoft Security Response Center US

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:Csecondary · ENISA EU

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · NVD / NIST USexploitability 1.8 · impact 5.9

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-416USprimaryCWE-264US

exploits (2)

Public proof-of-concept and weaponised exploit code.

KaLendsi/CVE-2021-34486Windows Etw LPEPoC · poc_in_github
b1tg/CVE-2021-34486-expb1tg/CVE-2021-34486-expPoC · poc_in_github

affected products (63)

Products and version ranges known to be affected.

Microsoft Windows 10 Version 180910.0.0 → 10.0.17763.2114enisa_euvdEU
Microsoft Windows 10 Version 180910.0.17763.0 → 10.0.17763.2114enisa_euvdEU
Microsoft Windows 10 Version 190910.0.0 → 10.0.18363.1734enisa_euvdEU
Microsoft Windows 10 Version 200410.0.0 → 10.0.19041.1165enisa_euvdEU
Microsoft Windows 10 Version 20H210.0.0 → 10.0.19042.1165enisa_euvdEU
Microsoft Windows 10 Version 21H110.0.0 → 10.0.19043.1165enisa_euvdEU
Microsoft Windows Server 201910.0.17763.0 → 10.0.17763.2114enisa_euvdEU
Microsoft Windows Server 2019 (Server Core installation)10.0.17763.0 → 10.0.17763.2114enisa_euvdEU
Microsoft Windows Server version 200410.0.0 → 10.0.19041.1165enisa_euvdEU
Microsoft Windows Server version 20H210.0.0 → 10.0.19042.1165enisa_euvdEU
Microsoft Corp Windows 10 1809all versionsfstec_bduRU
Microsoft Corp Windows 10 1909all versionsfstec_bduRU
Microsoft Corp Windows 10 2004all versionsfstec_bduRU
Microsoft Corp Windows 10 20H2all versionsfstec_bduRU
Microsoft Corp Windows 10 21H1all versionsfstec_bduRU
Microsoft Corp Windows Server 2004 (Server Core Installation)all versionsfstec_bduRU
Microsoft Corp Windows Server 2019all versionsfstec_bduRU
Microsoft Corp Windows Server 2019 (Server Core installation)all versionsfstec_bduRU
Microsoft Corp Windows Server 20H2 (Server Core Installation)all versionsfstec_bduRU
Windows 10 Version 1809 for 32-bit Systemsall versionsfixedmsrc_csafUS

showing 20 of 63

advisories (1)

Vendor and ecosystem advisories describing this.

msrc_CVE-2021-34486Windows Event Tracing Elevation of Privilege Vulnerability2021-08-10csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu msrc_csaf NVD CVE.org MITRE

published 2021-08-12modified 2026-08-10

related (12,135)

Related entries.

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Use after free in Dawn in Google Chrome prior to 146.0.7680.178 allowed a remote attacker who had compromised the renderer process to execute arbitrary code via a crafted HTML page…
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Use after free in CSS in Google Chrome prior to 145.0.7632.75 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security sever…
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A use-after-free issue was addressed with improved memory management. This issue is fixed in Safari 26.2, iOS 18.7.3 and iPadOS 18.7.3, iOS 26.2 and iPadOS 26.2, macOS Tahoe 26.2,…
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Use after free in Windows Cloud Files Mini Filter Driver allows an authorized attacker to elevate privileges locally.

+12130 more

references (9)

External citations — patches, advisories, analysis.

scry

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