CVE-2020-1356 — Windows iSCSI Target Service Elevation of Privilege Vulnerability

Executive Summary

An elevation of privilege vulnerability exists when the Windows iSCSI Target Service improperly handles file operations. An attacker who successfully exploited this vulnerability could gain elevated privileges. To exploit the vulnerability, an attacker would first need code execution on a victim system. An attacker could then run a specially crafted application. The security update addresses the vulnerability by ensuring the Windows iSCSI Target Service properly handles file operations.

Overview

7.8

CVSS HIGH

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Elevation of Privilege

Released Jul 14 2020

Last Updated Jul 14 2020

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.00708 — 0.48561 percentile

NVD CVSS 7.8 HIGH — matches MSRC

CVSS Vector

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

ATTACK VECTOR

Local

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

Low

USER INTERACTION

None

SCOPE

Unchanged

CONFIDENTIALITY

High

INTEGRITY

High

AVAILABILITY

High

EXPLOIT CODE MATURITY

Proof-of-Concept

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 7.0

EPSS Score

0.00708

probability of exploitation in the next 30 days

0.48561 percentile - updated 2026-06-21

View on FIRST.org

Affected Products

7 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows Server 2012 4565537 (Monthly Rollup) 4565535 (Security Only) Important Elevation of Privilege 4561612 Base: 7.8 Temporal: 7.0 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C Yes 4565537 4565535 Windows Server 2012 (Server Core installation) 4565537 (Monthly Rollup) 4565535 (Security Only) Important Elevation of Privilege 4561612 Base: 7.8 Temporal: 7.0 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C Yes 4565537 4565535 Windows Server 2012 R2 4565541 (Monthly Rollup) 4565540 (Security Only) Important Elevation of Privilege 4561666 Base: 7.8 Temporal: 7.0 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C Yes 4565541 4565540 Windows Server 2012 R2 (Server Core installation) 4565541 (Monthly Rollup) 4565540 (Security Only) Important Elevation of Privilege 4561666 Base: 7.8 Temporal: 7.0 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C Yes 4565541 4565540 Windows Server 2016	`4565511 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server 2016 (Server Core installation)	`4565511 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server 2019	`4558998 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server 2019 (Server Core installation)	`4558998 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server, version 1903 (Server Core installation)	`4565483 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server, version 1909 (Server Core installation)	`4565483 (Security Update)`	Important	Elevation of Privilege	Yes
Windows Server, version 2004 (Server Core installation)	`4565503 (Security Update)`	Important	Elevation of Privilege	Yes

Patches

4 patches

Article	Type	Restart
`4565511`	Security Update	Yes
`4558998`	Security Update	Yes
`4565483`	Security Update	Yes
`4565503`	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

Zhiniang Peng (@edwardzpeng) & Xuefeng Li

References

MSRC Advisory MITRE NVD