CVE-2021-1704 — Windows Hyper-V Elevation of Privilege Vulnerability

Executive Summary

None

Overview

7.3

CVSS HIGH

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Elevation of Privilege

Released Jan 12 2021

Last Updated Jan 12 2021

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.01008 — 0.59472 percentile

NVD CVSS 7.3 HIGH — matches MSRC

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

ATTACK VECTOR

Local

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

Low

USER INTERACTION

Required

SCOPE

Unchanged

CONFIDENTIALITY

High

INTEGRITY

High

AVAILABILITY

High

EXPLOIT CODE MATURITY

Unproven

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 6.4

EPSS Score

0.01008

probability of exploitation in the next 30 days

0.59472 percentile - updated 2026-07-25

View on FIRST.org

Affected Products

14 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows 10 for x64-based Systems	`4598231 (Security Update)`	Important	Elevation of Privilege	Yes
Windows 10 Version 1607 for x64-based Systems	`4598243 (Security Update)`	Important	Elevation of Privilege	Yes
Windows 10 Version 1803 for x64-based Systems	`4598245 (Security Update)`	Important	Elevation of Privilege	Yes
Windows 10 Version 1809 for x64-based Systems	`4598230 (Security Update)`	Important	Elevation of Privilege	Yes
Windows 10 Version 1909 for x64-based Systems	`4598229 (Security Update)`	Important	Elevation of Privilege	Yes
Windows 10 Version 2004 for x64-based Systems	`4598242 (Security Update)`	Important	Elevation of Privilege	Yes
Windows 10 Version 20H2 for x64-based Systems	`4598242 (Security Update)`	Important	Elevation of Privilege	Yes
Windows 7 for x64-based Systems Service Pack 1 4598279 (Monthly Rollup) 4598289 (Security Only) Important Elevation of Privilege 4592471 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598279 4598289 Windows 8.1 for x64-based systems 4598285 (Monthly Rollup) 4598275 (Security Only) Important Elevation of Privilege 4592484 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598285 4598275 Windows Server 2008 for x64-based Systems Service Pack 2 4598288 (Monthly Rollup) 4598287 (Security Only) Important Elevation of Privilege 4592498 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598288 4598287 Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation) 4598288 (Monthly Rollup) 4598287 (Security Only) Important Elevation of Privilege 4592498 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598288 4598287 Windows Server 2008 R2 for x64-based Systems Service Pack 1 4598279 (Monthly Rollup) 4598289 (Security Only) Important Elevation of Privilege 4592471 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598279 4598289 Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) 4598279 (Monthly Rollup) 4598289 (Security Only) Important Elevation of Privilege 4592471 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598279 4598289 Windows Server 2012 4598278 (Monthly Rollup) 4598297 (Security Only) Important Elevation of Privilege 4592468 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598278 4598297 Windows Server 2012 (Server Core installation) 4598278 (Monthly Rollup) 4598297 (Security Only) Important Elevation of Privilege 4592468 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598278 4598297 Windows Server 2012 R2 4598285 (Monthly Rollup) 4598275 (Security Only) Important Elevation of Privilege 4592484 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598285 4598275 Windows Server 2012 R2 (Server Core installation) 4598285 (Monthly Rollup) 4598275 (Security Only) Important Elevation of Privilege 4592484 Base: 7.3 Temporal: 6.4 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C Yes 4598285 4598275 Windows Server 2016	`4598243 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server 2016 (Server Core installation)	`4598243 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server 2019	`4598230 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server 2019 (Server Core installation)	`4598230 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server, version 1909 (Server Core installation)	`4598229 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server, version 2004 (Server Core installation)	`4598242 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server, version 20H2 (Server Core Installation)	`4598242 (Security Update)`	Important	Elevation of Privilege	Yes

Patches

6 patches

Article	Type	Restart
`4598231`	Security Update	Yes
`4598243`	Security Update	Yes
`4598245`	Security Update	Yes
`4598230`	Security Update	Yes
`4598229`	Security Update	Yes
`4598242`	Security Update	Yes

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

@EranShimony CyberaArk

References

MSRC Advisory MITRE NVD